fix: MCP tools not surfacing after Sync to Nodes, update Anthropic to… (#272)

* fix: MCP tools not surfacing after Sync to Nodes, update Anthropic tool search

Three fixes:

1. session_factory closure captured mcp_client=None when no --mcp-config
   was passed at startup. internal_mcp_reload created a new MCPClientManager
   on app.state but the factory never saw it. New workstreams got 0 MCP tools.
   Fix: mutable _mcp_ref list shared between factory and reload handler.

2. Anthropic dropped the date suffix from tool_search_tool_bm25_20251119
   and now requires name == type. Updated constant and tool definition.

3. Add diagnostic logging around API errors (provider, model, base_url,
   message counts, full exception chain) and workstream resume (pre/post
   provider state, alias resolution warnings).

Also adds Node.js 24 LTS to Dockerfile via multi-stage copy for npx-based
MCP servers.

* fix: address Copilot review — set_storage on reload, sanitize log output

- Call mcp_mgr.set_storage(storage) when internal_mcp_reload creates a
  new MCPClientManager so prompt sync works for post-startup servers
- Strip query params from base_url before logging (may contain API keys
  in some vLLM deployments)
- Split API error logging: concise warning (type names only) + separate
  debug with exc_info=True for full traceback when needed

* chore: remove DDG MCP sidecar, web_search uses built-in ddgs client

The DuckDuckGo MCP server container is redundant — the built-in
DuckDuckGoClient (via ddgs package, included in all extras) auto-detects
when no Tavily key is configured. Removes the ddg-search service,
ddgCluster profile, and mcp-ddg.json config file.

Dockerfile

@@ -18,6 +18,12 @@ RUN apt-get update && apt-get upgrade -y && apt-get install -y --no-install-reco
     libpq5 git curl jq man-db manpages procps file \
     && rm -rf /var/lib/apt/lists/*
 
+# Node.js LTS (for npx-based MCP servers like @modelcontextprotocol/server-github)
+COPY --from=node:24-slim /usr/local/bin/node /usr/local/bin/node
+COPY --from=node:24-slim /usr/local/lib/node_modules /usr/local/lib/node_modules
+RUN ln -s ../lib/node_modules/npm/bin/npm-cli.js /usr/local/bin/npm \
+    && ln -s ../lib/node_modules/npm/bin/npx-cli.js /usr/local/bin/npx
+
 # Non-root user
 RUN useradd --create-home --shell /bin/bash turnstone