[Plan] Fix MCP shared spawn

[github-actions]

Overview

Document the MCP Inspector reconnect loop in openadt-mcp 1.3.16 (broken cold-start shared backend from compiled .exe), distinguish it from the earlier June initialize/transport fixes, and fix spawnDetachedServe to re-exec the packaged binary via process.execPath.

Tasks

• Merge/rebase local branch onto origin/main (ensure-backend.ts present)
• Update specs/mcp-shared-backend.md (+ mcp.md) with packaged vs dev spawn rules
• Implement resolveDetachedSpawn() and refactor spawnDetachedServeInternal to use process.execPath for packaged binary
• Add ensure-backend.test.ts cases for packaged/dev/explicit launcher paths
• Manual test: openadt-mcp serve --stdio cold start with Content-Length initialize + MCP Inspector
• Release v1.3.17 with rebuilt openadt-mcp Scoop/Homebrew artifacts

Plan

.cursor/plans/fix_mcp_shared_spawn_0d3630bb.plan.md

Auto-created from a Cursor plan via the plan-sync workflow.