feat: implement server/discover method on stdio and HTTP transports

[github-actions]

Closes #97

Implements the server/discover JSON-RPC method on both transports so MCP 2026-07-28 clients can classify this server deterministically as legacy-only instead of inferring it from a -32601 method not found.

What changed

• mcp_server.go — added mcpProtocolVersion, mcpSupportedProtocolVersions, and the shared buildInitializeResult() / buildDiscoverResult() helpers, so the two transports build the same payload and can't drift. New case "server/discover" in the stdio dispatcher.
• mcp_http.go — initialize now uses buildInitializeResult(); new case "server/discover" returns buildDiscoverResult(). The method is also exempt from the unrecognized-session 404 in httpHandlePost, since a modern client probes before it has a session and a stale header must not turn an era classification into a not-found.

Response shape:

{
  "protocolVersion": "2025-03-26",
  "supportedProtocolVersions": ["2025-03-26"],
  "capabilities": { "tools": {}, "resources": {}, "prompts": {} },
  "serverInfo": { "name": "convctl-mcp", "version": "<mcpServerVersion>" }
}

Out of scope as specified: no 2026 stateless semantics, no extension advertising, no session-management changes, no UnsupportedProtocolVersionError from initialize. initialize behaviour is unchanged. No capabilities.extensions: {} — an empty map signals nothing.

Tests

• TestMCPProtocol_ServerDiscover (stdio) — probes server/discover before any handshake, asserts supportedProtocolVersions, then compares protocolVersion / capabilities / serverInfo byte-for-byte against a subsequent initialize.
• TestHTTPDispatch_ServerDiscover — same assertions through httpDispatch.
• TestHTTPHandlePost_ServerDiscover_NoSessionRequired and ..._ExemptFromSessionCheck — 200 with no session header, and 200 with a stale one.

go build ./..., go vet ./... and go test -race ./... are clean (full package, 58.9% coverage).

Version

Bumped to 2.10.1 across the manifests, with a CHANGELOG entry. plugins/corezoid/.kiro-plugin/plugin.json was stranded at 2.9.0 by the 2.10.0 release (CI only checks the other four) — realigned here.

🤖 Generated with Claude Code

[gh-corezoid]

AI Review

Adds server/discover JSON-RPC on both stdio and HTTP transports so MCP 2026-07-28 clients can classify this server as legacy-only without relying on a -32601 error; bumps the plugin to 2.10.1 and realigns .kiro-plugin/plugin.json which was stranded at 2.9.0.

Checklist

Check	Result
U1 — Conventional commit format	⚠️ warning
U2 — No leaked credentials	✅ pass
U3 — No merge commits	✅ pass
U4 — PR targets correct base branch (main)	✅ pass
U5 — Build & tests (Go)	✅ pass
U6 — Architectural & design consequences	⚠️ warning (pre-existing)
C1 — All four manifest files version-synced	✅ pass
C2 — Node IDs in .conv.json files	⏭️ skip (no .conv.json changed)
C3 — No hardcoded env-specific values in .conv.json	⏭️ skip
C4 — extra fields have matching extra_type	⏭️ skip
C5 — README updated for new skills	⏭️ skip (no new skill directories)

Issues found

[warning] U1 — bump to X.Y.Z missing from commit subject line
The single commit feat(mcp-server): implement server/discover on stdio and HTTP touches four version manifests (all bumped to 2.10.1) but the subject line does not include the trailing , bump to 2.10.1 required by the project's conventional-commit convention. The bump is documented clearly in the commit body, so the intent is unambiguous — but future tooling that parses only the headline (changelogs, release-note automation) may silently omit it.
Fix: rename the commit subject to feat(mcp-server): implement server/discover on stdio and HTTP, bump to 2.10.1.

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[warning] U6 — mcpServerVersion constant out of sync with plugin version (pre-existing)
mcp_server.go:53 has const mcpServerVersion = "2.3.5" with a comment "Keep this in sync with .claude-plugin/plugin.json", but the manifests are at 2.10.1. This discrepancy predates this PR and is not introduced by it; the serverInfo.version field in every initialize and server/discover response therefore reports 2.3.5 to clients. Flagging here because the new buildDiscoverResult() prominently surfaces serverInfo and makes the mismatch more visible to MCP 2026-07-28 clients that inspect the discovery payload.
Fix (separate PR): align mcpServerVersion with the current plugin version or intentionally decouple the two and document the difference.

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This review was generated automatically. A human maintainer should still make the merge decision.