refactor(element): remove dead v0.43 renderer/hydration residue (#1273 O2, B2.13)

Dead-code proof (import graph from every deno.json exports entrypoint +
CLI/bin entries, plus repo-wide symbol search incl. tests, www, tools,
examples): zero consumers for each removal. All five deleted modules were
shipped to npm because every package publishes src/**.

Deleted:
- src/types.ts (ElementDefinition render()->VNode typing of the removed
  runtime renderer)
- src/internal/protocol/vnode.ts (VNode/ComponentFn/ComponentCtor/RenderFn)
- src/internal/protocol/prop.ts (ADR-0052 static prop-decl typing,
  superseded by compiler __compiledProperties)
- src/internal/core/dom-utils.ts (clearChildren, unused since #902-era
  renderer removal)
- src/internal/core/dsd-shadow-root.ts (hasPopulatedShadowRoot, unused)

Slimmed:
- internal/protocol/render.ts: dropped the legacy DSD-pipeline interfaces
  (RenderPhase, RenderInput, RenderHooks, DsdOptions, RenderErrorCode,
  DsdComponentConstructor, DsdComponent) and the VNode import; kept the
  live RenderError/RenderOutput/HydrationHint/DsdRenderMetrics/
  SsrAdmissionDecision contract unchanged (snapshot shapes identical).
- internal/protocol/hydration-markers.ts: removed the v0.43 marker
  constants (DATA_SIGNAL*, DATA_EID, DATA_SSR_PROPS, BRANCH_MARKER_PREFIX,
  FOR_ITEM_PREFIX, FOR_END_PREFIX) and parseSignalAttrSpec. The compiled
  model claims through oe:pN program anchors; the marker literals are
  already forbidden in built artifacts by check-v044-legacy-absence.ts.
  DATA_OE_LIGHT stays: it is the live ADR-0142 light-mode marker, consumed
  via literals across the generated-code boundary by design.

Public surface: DATA_SSR_PROPS re-export removed from src/index.ts and
src/public-runtime.ts. The data-ssr-props channel was already documented
as gone (app/preact.ts); the export was classed internal-importable, had
no consumer anywhere in the repo, and is deleted rather than deprecated
per the B2.13 removal authority. Interface snapshot, package-surface
class map and content graph regenerated; the only snapshot delta is the
DATA_SSR_PROPS symbol removal.

Also fixes the stale reader list in ssr-registry-markers.ts (element's
define-element.ts no longer exists; the SSR stub marker is read by
app/preact.ts).

Refs #1273. Stage #1288 risk #8.

Author: DevBot

docs/current/PACKAGE_SURFACE.md

@@ -183,7 +183,6 @@ classified name missing from the prose fails the gate.
       "createContext": "stable-candidate",
       "createLogger": "internal-importable",
       "DANGEROUS_KEYS": "experimental",
-      "DATA_SSR_PROPS": "internal-importable",
       "deepGetElementById": "internal-importable",
       "effect": "stable-candidate",
       "element": "experimental",
@@ -467,7 +466,7 @@ classified name missing from the prose fails the gate.
 | ----------------- | ------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | root              | compatibility-only  | `OpenElementRouteKind`, `OpenElementRouteNode`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
 |                   | experimental        | `DANGEROUS_KEYS`, `element`, `injectPropsSafe`, `isDangerousKey`, `property`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
-|                   | internal-importable | `AppShellConfig`, `assertValidTagName`, `collectPublicProps`, `CompatibilityClassification`, `CompatibilityTier`, `ComponentLayer`, `createLogger`, `DATA_SSR_PROPS`, `deepGetElementById`, `ensureDeepFragmentNavigation`, `ensurePreHydrationClickCapture`, `formatError`, `FrameworkOptions`, `isValidTagName`, `renderDsd`, `RenderDsdOptions`, `RenderOutput`, `RouteEntry`, `SpecialFileType`, `SsrAdmissionDecision`, `wrapInDocument`                                                                                                                                                                                                                                                                                                                                                                                                                              |
+|                   | internal-importable | `AppShellConfig`, `assertValidTagName`, `collectPublicProps`, `CompatibilityClassification`, `CompatibilityTier`, `ComponentLayer`, `createLogger`, `deepGetElementById`, `ensureDeepFragmentNavigation`, `ensurePreHydrationClickCapture`, `formatError`, `FrameworkOptions`, `isValidTagName`, `renderDsd`, `RenderDsdOptions`, `RenderOutput`, `RouteEntry`, `SpecialFileType`, `SsrAdmissionDecision`, `wrapInDocument`                                                                                                                                                                                                                                                                                                                                                                                                                                                |
 |                   | stable-candidate    | `Action`, `ACTION_FETCH_HEADER`, `ActionContext`, `ActionResult`, `computed`, `consumeContext`, `Context`, `createContext`, `effect`, `ERROR_PREFIX`, `ErrorBoundary`, `ErrorTelemetryHook`, `escapeAttr`, `escapeHtml`, `HYDRATION_STRATEGIES`, `HydrationStrategy`, `IslandOptions`, `isSafeAttributeName`, `Loader`, `LoaderContext`, `LocalePath`, `Middleware`, `OpenElement`, `OpenElementAttribute`, `OpenElementCssPart`, `OpenElementDeclaration`, `OpenElementError`, `OpenElementEvent`, `OpenElementPackageManifest`, `OpenElementSlot`, `PROBLEM_JSON_MEDIA_TYPE`, `ProblemDetails`, `provideContext`, `RenderError`, `reportError`, `ServerRouteContext`, `ServerRouteMetadata`, `setErrorTelemetryHook`, `signal`, `Signal`, `SpaAction`, `SpaActionContext`, `SpaLoader`, `SpaLoaderContext`, `StyleSheet`, `StyleSheetLike`, `trustedHtml`, `TrustedHtml` |
 | `jsx-runtime`     | stable-candidate    | `Fragment`, `jsx`, `JSX`, `jsxs`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
 | `jsx-dev-runtime` | stable-candidate    | `Fragment`, `JSX`, `jsxDEV`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |

docs/release/public-interface-snapshot.json

@@ -12,7 +12,7 @@
       },
       "declarations": {
         ".": {
-          "publicShapeSha256": "91ae10b67582b58198720342b1d5e7065af882d94215f04bac7f1adea002c671",
+          "publicShapeSha256": "c91c79a068bef242e7dd46601efc9fdd12084c77a8e2bc14b20e26f7c5905a7b",
           "publicSymbols": [
             "ACTION_FETCH_HEADER=value:\"x-openelement-action\"",
             "Action=type:{call:(ctx:{env:Env;formData:FormData;params:Record<string, string>;platform:union(Platform|undefined);request:Request;responseHeaders:Headers;route:Route})=>union(Promise<T>|T)}",
@@ -24,7 +24,6 @@
             "ComponentLayer=type:union(\"dsd-interactive\"|\"dsd-static\"|\"light-dom\"|\"pure-island\")",
             "Context=type:{readonly defaultValue:T;readonly key:symbol}",
             "DANGEROUS_KEYS=value:ReadonlySet<string>",
-            "DATA_SSR_PROPS=value:\"data-ssr-props\"",
             "ERROR_PREFIX=value:\"[openElement]\"",
             "ErrorBoundary=type:{_errors:{capture:{call:(error:unknown,source:unknown)=>void};catchError:{call:(error:unknown,source:unknown)=>void};dispose:{call:()=>void};error:union(null|{readonly code:string;readonly phase:union(\"build\"|\"csr\"|\"navigation\"|\"render\"|\"ssr\"|\"unknown\"|\"validation\");readonly recoverable:union(false|true);readonly severity:union(\"error\"|\"warning\");readonly statusCode?:union(number|undefined);toJSON:{call:()=>Record<string, unknown>}});hasError:union(false|true);maxRetries:number;reset:{call:()=>void};retry:{call:(recover:union(undefined|{call:()=>void}))=>union(false|true)};retryCount:number;source:unknown};_getLocale:{call:(fallback:string)=>string};_internals:union(ElementInternals|undefined);_lifecycleSignal:{call:()=>AbortSignal};_requestAnimationFrame:{call:(callback:FrameRequestCallback)=>number};_setTimeout:{call:(handler:union(Function|string),timeout:union(number|undefined))=>number};adoptedCallback:{call:()=>void};attributeChangedCallback:{call:(name:string,_oldValue:union(null|string),newValue:union(null|string))=>void};catchError:{call:(error:Error,source:unknown)=>void};clientActivate:{call:()=>void};connectedCallback:{call:()=>void};disconnectedCallback:{call:()=>void};error:union(null|{readonly code:string;readonly phase:union(\"build\"|\"csr\"|\"navigation\"|\"render\"|\"ssr\"|\"unknown\"|\"validation\");readonly recoverable:union(false|true);readonly severity:union(\"error\"|\"warning\");readonly statusCode?:union(number|undefined);toJSON:{call:()=>Record<string, unknown>}});formAssociatedCallback:{call:(_form:union(HTMLFormElement|null))=>void};formResetCallback:{call:()=>void};formStateRestoreCallback:{call:(state:union(File|FormData|null|string),mode:string)=>void};hasError:union(false|true);locale?:union(string|undefined);maxRetries:number;onCsrRendered:{call:()=>void};onDsdHydrated:{call:()=>void};params:Record<string, string>;reset:{call:()=>void};retry:{call:()=>void};retryCount:number}|value:{_resetGlobalStyles:{call:()=>void};client?:union(undefined|{hydrate?:union(\"idle\"|\"load\"|\"only\"|\"visible\"|undefined)});construct:()=>{_errors:{capture:{call:(error:unknown,source:unknown)=>void};catchError:{call:(error:unknown,source:unknown)=>void};dispose:{call:()=>void};error:union(null|{readonly code:string;readonly phase:union(\"build\"|\"csr\"|\"navigation\"|\"render\"|\"ssr\"|\"unknown\"|\"validation\");readonly recoverable:union(false|true);readonly severity:union(\"error\"|\"warning\");readonly statusCode?:union(number|undefined);toJSON:{call:()=>Record<string, unknown>}});hasError:union(false|true);maxRetries:number;reset:{call:()=>void};retry:{call:(recover:union(undefined|{call:()=>void}))=>union(false|true)};retryCount:number;source:unknown};_getLocale:{call:(fallback:string)=>string};_internals:union(ElementInternals|undefined);_lifecycleSignal:{call:()=>AbortSignal};_requestAnimationFrame:{call:(callback:FrameRequestCallback)=>number};_setTimeout:{call:(handler:union(Function|string),timeout:union(number|undefined))=>number};adoptedCallback:{call:()=>void};attributeChangedCallback:{call:(name:string,_oldValue:union(null|string),newValue:union(null|string))=>void};catchError:{call:(error:Error,source:unknown)=>void};clientActivate:{call:()=>void};connectedCallback:{call:()=>void};disconnectedCallback:{call:()=>void};error:union(null|{readonly code:string;readonly phase:union(\"build\"|\"csr\"|\"navigation\"|\"render\"|\"ssr\"|\"unknown\"|\"validation\");readonly recoverable:union(false|true);readonly severity:union(\"error\"|\"warning\");readonly statusCode?:union(number|undefined);toJSON:{call:()=>Record<string, unknown>}});formAssociatedCallback:{call:(_form:union(HTMLFormElement|null))=>void};formResetCallback:{call:()=>void};formStateRestoreCallback:{call:(state:union(File|FormData|null|string),mode:string)=>void};hasError:union(false|true);locale?:union(string|undefined);maxRetries:number;onCsrRendered:{call:()=>void};onDsdHydrated:{call:()=>void};params:Record<string, string>;reset:{call:()=>void};retry:{call:()=>void};retryCount:number};delegatesFocus?:union(false|true|undefined);formAssociated?:union(false|true|undefined);getGlobalStyles:{call:()=>array({readonly cssRules:array({cssText:string});replaceSync:{call:(text:string)=>void}})};head?:union(undefined|{description?:union(string|undefined);ogImage?:union(string|undefined);title?:union(string|undefined)});isErrorBoundary:union(false|true);registerGlobalStyles:{call:(sheets:unknown)=>void};renderMode?:union(\"light\"|\"shadow\"|undefined);styles?:union(array({readonly cssRules:array({cssText:string});replaceSync:{call:(text:string)=>void}})|undefined|{readonly cssRules:array({cssText:string});replaceSync:{call:(text:string)=>void}})}",
             "ErrorTelemetryHook=type:{call:(error:{readonly code:string;readonly phase:union(\"build\"|\"csr\"|\"navigation\"|\"render\"|\"ssr\"|\"unknown\"|\"validation\");readonly recoverable:union(false|true);readonly severity:union(\"error\"|\"warning\")})=>void}",

packages/element/src/index.ts

@@ -80,12 +80,6 @@ export { DANGEROUS_KEYS, injectPropsSafe, isDangerousKey } from './public-runtim
 
 export type { IslandOptions } from './public-runtime.ts';
 
-// ─── Hydration markers (protocol) ───────────────────────
-
-// Shared by SSR writers and client readers (app, www) so the attribute name
-// has a single typed source (#836).
-export { DATA_SSR_PROPS } from './public-runtime.ts';
-
 // ─── StyleSheet (re-export from core) ────────────────────
 
 export {

packages/element/src/internal/protocol/hydration-markers.ts

@@ -1,34 +1,19 @@
 /**
- * hydration-markers.ts - DSD hydration marker contract.
+ * hydration-markers.ts - light-mode SSR provenance marker contract.
  *
- * These constants and helpers define the canonical shape of the markers used
- * to re-connect signals and events between SSR output and client-side hydration.
+ * The v0.43 marker-based hydration channel (`data-signal*`, `data-eid`,
+ * `data-ssr-props`, `oe-branch:`/`oe-for-item:` comments) was removed with the
+ * compiled Part Program model: claim now binds through program anchors
+ * (`oe:pN`, internal/compiled/program.ts), and the legacy marker strings are
+ * forbidden in built artifacts by tools/check-v044-legacy-absence.ts.
  *
- * Keep marker string values stable: they are persisted in serialized HTML and
- * read by hydration code in `../core/index.ts` and `@openelement/element`.
+ * One marker survives. Its consumers (internal/compiled/server,
+ * internal/compiled/runtime, and the adapter's SSG/dev toolchain) reference
+ * the string literal by design — the writer/reader set crosses the
+ * generated-code boundary, so there is no import edge; this module is the
+ * single source for the name so a rename cannot drift silently.
  */
 
-/** Marker that binds a named signal to an element's textContent. */
-export const DATA_SIGNAL = 'data-signal';
-
-/** Marker that lists the HTML attributes a signal drives on an element. */
-export const DATA_SIGNAL_ATTR = 'data-signal-attr';
-
-/** Marker that toggles a single CSS class based on a signal's truthiness. */
-export const DATA_SIGNAL_CLASS = 'data-signal-class';
-
-/** Marker that replaces an element's children with a signal's VNode value. */
-export const DATA_SIGNAL_RENDER = 'data-signal-render';
-
-/** Marker that identifies an element carrying serialized event bindings. */
-export const DATA_EID = 'data-eid';
-
-/**
- * Marker carrying the JSON-serialized public props of an SSR-rendered host,
- * read back on client upgrade to restore component state (#836).
- */
-export const DATA_SSR_PROPS = 'data-ssr-props';
-
 /**
  * Internal SSR provenance marker on light-mode host tags (ADR-0142, #1148).
  *
@@ -38,34 +23,3 @@ export const DATA_SSR_PROPS = 'data-ssr-props';
  * subtree. Client rendering never writes it and it is never removed.
  */
 export const DATA_OE_LIGHT = 'data-oe-light';
-
-/** HTML comment prefix recording the SSR-evaluated branch state of `<Show>`/`<For>`. */
-export const BRANCH_MARKER_PREFIX = 'oe-branch:';
-
-/**
- * HTML comment prefix emitted by SSR before each `<For>` item, in traversal
- * order (value = item ordinal). Hydration (matched path) slices the seeded
- * list regions between consecutive markers so keyed reconciliation can take
- * over the existing SSR DOM instead of re-rendering it (#917).
- */
-export const FOR_ITEM_PREFIX = 'oe-for-item:';
-
-/** HTML comment emitted by SSR after a `<For>`'s last item (region terminator). */
-export const FOR_END_PREFIX = 'oe-for-end';
-
-/** Parsed value of a `data-signal-attr` attribute: a list of attribute names. */
-type SignalAttrSpec = string[];
-
-/**
- * Parse a `data-signal-attr` marker value into individual attribute names.
- *
- * The value is a comma-separated list (e.g. `"class,disabled"`). Empty entries
- * and surrounding whitespace are ignored, preserving the original attribute
- * order.
- *
- * @param value - Raw marker value from the DOM.
- * @returns Non-empty attribute names.
- */
-export function parseSignalAttrSpec(value: string): SignalAttrSpec {
-  return value.split(',').map((part) => part.trim()).filter(Boolean);
-}