refactor(element,tools): B2.13 cleanup — #1273 O1/O2 + dead v0.43 residue audit gate

[SisyphusZheng]

Problem

Issue #1273 records two observations from the v0.44 hostile admission audit
(docs/evidence/2026-09-03-v044-hostile-admission-audit.md):

• O1: route-manifest.ts documented the catch-all file convention as
  /products/* while the tested behavior is the Hono named-regex parameter
  /products/:slug{.+} (route-manifest.test.ts:144).
• O2 (D13): the legacy marker-hydration constants (data-signal*,
  data-eid, oe-branch:, oe-for-item:) and the public DATA_SSR_PROPS
  re-export outlive their removed channel — the compiled model claims through
  oe:pN program anchors, and app/preact.ts already documents the
  data-ssr-props channel as gone.

Stage risk #8 on #1288 additionally asks: what do the published v0.44 package
artifacts ship that the v0.44 execution/authoring model no longer consumes?
Every package publishes src/**, so any dead source module goes straight to
npm.

Owner

Single-owner cleanup: @openelement/element internal protocol/core modules
plus one adapter doc comment. No architectural ownership moves.

Before

• Catch-all doc comment described /products/* (never the tested semantics).
• DATA_SSR_PROPS publicly exported from @openelement/element root,
  classed internal-importable, zero consumers repo-wide.
• Five proven-dead modules shipped in the packed @openelement/element
  tarball (see audit table).
• No gate stopped dead v0.43 modules/markers from re-entering published
  artifacts.

After

• Doc comment matches the tested /products/:slug{.+} semantics.
• DATA_SSR_PROPS re-export removed; the five dead modules deleted;
  hydration-markers.ts slimmed to the one live marker (DATA_OE_LIGHT,
  ADR-0142) with a corrected contract header; render.ts slimmed to its live
  types (public RenderOutput/SsrAdmissionDecision shapes unchanged).
• check-package-artifacts.ts (already ci+release tier, runs on the packed
  tarballs) now rejects the deleted paths and the removed marker-channel
  strings in packed sources.

Why-not-second-owner

No second implementation or owner exists: the audit's D13 classified the
markers as an observation, not a live duplicate. The compiled Part Program
runtime (internal/compiled/*) is the single reactive/SSR path; nothing here
creates or moves an owner.

Residue audit (stage #1288 risk #8)

Method: import-graph reachability from every deno.json exports entrypoint
and CLI/bin entry of all five published packages, plus repo-wide symbol
search (rg) over packages/, www/, tools/, examples/, e2e/
including all test dirs; cross-checked against the packed tarball file list
(pack:dry-run), the public-interface snapshot, and PACKAGE_SURFACE.md.
Hits in e2e/starter-smoke/work/deps/ are stale copies of an old published
package, not consumers.

Candidate	Verdict	Proof
element/src/types.ts (ElementDefinition, render(): VNode)	deleted	zero importers repo-wide; not in any exports map, snapshot, or surface class list; legacy runtime-renderer typing
element/src/internal/protocol/vnode.ts (VNode & friends)	deleted	only importers were types.ts (deleted) and render.ts's DsdComponent (removed); no other consumer
element/src/internal/protocol/prop.ts (PropDecl*, PropsFrom)	deleted	zero importers repo-wide; superseded by compiler __compiledProperties metadata
element/src/internal/core/dom-utils.ts (clearChildren)	deleted	zero importers incl. tests; call sites use replaceChildren() directly
element/src/internal/core/dsd-shadow-root.ts (hasPopulatedShadowRoot)	deleted	zero importers incl. tests
hydration-markers.ts legacy constants + parseSignalAttrSpec	deleted	zero importers; the marker literals (data-eid, data-signal*, oe-branch:, oe-for-item:) are already forbidden in built artifacts by check-v044-legacy-absence.ts; claim uses oe:pN anchors
DATA_SSR_PROPS public re-export (index.ts, public-runtime.ts)	deleted	zero importers repo-wide; channel documented gone (app/preact.ts:14); classed internal-importable, not stable; snapshot + surface + content-graph regenerated (only delta: this symbol)
render.ts: RenderPhase, RenderInput, RenderHooks, DsdOptions, RenderErrorCode, DsdComponentConstructor, DsdComponent	deleted	zero consumers repo-wide; live renderDsd carries its own RenderDsdOptions in public-runtime.ts; remaining public shapes byte-identical in the snapshot
hydration-markers.ts DATA_OE_LIGHT	kept	live ADR-0142 light-mode SSR marker; consumed as a string literal across the generated-code boundary by design (compiled server/runtime, adapter toolchain); module is the chartered name source (same pattern as ssr-registry-markers.ts)
element/src/internal/protocol/ssr-registry-markers.ts	kept	chartered #965 SSR-registry stub marker contract; no import edge by design (writer is generated code); stale reader list in its header corrected (define-element.ts no longer exists)
adapter-vite: enhance-client.ts, form-enhance.ts, morph-align.ts, morph-focus-restore.ts, morph-scroll-restore.ts, morph-webkit-fix.ts, island-lifecycle.ts, island-scheduler.ts	kept	not statically reachable from exports because they are bundled browser runtimes: dev-island-client.ts:69-72 and cli/build-client.ts:534-537 resolve them by file path via virtual:open-client-runtime (#868); form-enhance.ts/morph-* are additionally ADR-0122 frozen
render.ts live types (RenderError, RenderOutput, HydrationHint, DsdRenderMetrics, SsrAdmissionDecision)	kept	publicly re-exported (RenderOutput, SsrAdmissionDecision) or imported by the error protocol (RenderError); snapshot-pinned
app/ui/create packages	no residue found	reachability from exports covers 100% of their shipped src/** files

Anti-regression gate

tools/check-package-artifacts.ts (runs pack:dry-run, then scans the
extracted tarballs; gated at ci+release tiers in tools/autoflow/policy.ts,
triggered by any packages/** change):

• FORBIDDEN_LEGACY_PATHS — the five deleted modules fail the gate if they
  reappear in a packed artifact.
• FORBIDDEN_LEGACY_SOURCE_PATTERNS — DATA_SSR_PROPS, data-eid/
  data-signal* attribute strings and oe-branch:/oe-for-item: comment
  markers are rejected in comment-stripped packed sources, extending the
  check-v044-legacy-absence.ts dist contract to the published src/**
  payload.

Unit tests cover both rules plus comment/other-package false-positive guards
(tools/check-package-artifacts.test.ts, 3 new tests).

Evidence

All at branch tip on macOS arm64, Deno 2.x:

• deno task test → exit 0 (ok | 1870 passed (105 steps) | 0 failed | 1 ignored; supabase starter suite 150 passed | 0 failed)
• deno task interface:snapshot → exit 0 (regenerated; sole delta is the
  DATA_SSR_PROPS symbol removal)
• deno task package-surface:check → exit 0
• deno task content-graph:check / api-reference:check → exit 0
  (byte-identical regeneration)
• deno task graph:check / export-files:check → exit 0
• deno task freeze:semantics:check → no frozen path touched by this change
  (verified against FROZEN_PATHS; no ADR-0151 citation required)
• deno task package-artifacts:check (includes pack:dry-run, publint,
  attw) → exit 0 for all 5 packages
• deno lint / deno fmt --check on all touched files → clean

Packed-artifact diff (intentional, recorded): @openelement/element
tarball loses exactly src/types.ts, src/internal/protocol/vnode.ts,
src/internal/protocol/prop.ts, src/internal/core/dom-utils.ts,
src/internal/core/dsd-shadow-root.ts; src/internal/protocol/render.ts,
src/internal/protocol/hydration-markers.ts, src/index.ts,
src/public-runtime.ts shrink. Verified via tar -tzf on the dry-run
tarball (118 entries; none of the deleted paths present). Other four
packages: no content change (adapter-vite ships the corrected comment only).

Scope

In: #1273 O1/O2, B2.13 residue audit + gate. Out: no compiler/Part
Program/runtime/public-architecture redesign; no ADR-0122 frozen path
touched; adapter browser runtimes and charter modules kept with documented
proof.

Risk

Low. Every deletion is backed by zero-consumer proof across the repo and the
packed artifact; the public-surface delta is one internal-importable symbol
whose channel is already documented as removed. External deep imports of
deleted modules are not part of the supported surface (not in any exports
map). If a downstream pin relied on DATA_SSR_PROPS, the constant's value
was the string 'data-ssr-props' from a channel that no runtime reads.

Closes #1273. Stage #1288 risk #8.