fix(mcp): stop advertising tool list changes - #466

Summary

Stops the docs.plus MCP connector from advertising tools.listChanged when its tool set is fixed.

@modelcontextprotocol/[email protected] defaults tools.listChanged to true. Because docs.plus registers its document and chat tools once per request and never changes them afterward, newer MCP clients may otherwise open a subscriptions/listen stream that can never carry a tool-list notification.

This change explicitly sets capabilities: { tools: { listChanged: false } } when constructing the McpServer, with a comment explaining why.

Related issue

Closes #460

Type of change

• Bug fix
• New feature
• Refactor
• Documentation update
• CI/CD or tooling change

How to test

Per #460:

1. From apps/hocuspocus.server, run bun run typecheck && bun test.
2. Build a server through createServerFactory with stub dependencies and inspect server.server.getCapabilities().tools.
3. Expected result: { listChanged: false }.

Checklist

• I ran bun run check:ci (local replica of the prod quality gates).
• I tested the change locally.
• I added/updated tests where needed. No committed test is required by Stop advertising tools.listChanged on the MCP connector #460; its verification specifies the existing package suite plus a throwaway capability readback.
• I updated related documentation where needed. Stop advertising tools.listChanged on the MCP connector #460 lists docs as out of scope because no docs currently describe this capability.
• This PR is focused and does not include unrelated changes.

Local Bun execution was not available in the environment used to prepare this contribution, so the executable package checks are intentionally left unchecked rather than overstated.