Features
- list_docs returns a nested default block matching config.default
  (docs, embedding_model, top_k, chunk_max_chars) instead of
  flat default_docs.

Docs
- AGENTS.md requires syncing server.json on version bumps and
  committing it with pyproject.toml and uv.lock.

CI
- Bump actions/checkout and astral-sh/setup-uv for Node 24 runners.