Add per-tool in-memory call counters to the MCP module and a
GET /api/v1/status/mcp endpoint that joins them with the live tool
registry and endpoint config, then render it as a new card on the
System Status page with a one-click client-config copy button.
- app/mcp/stats.py: lock-guarded MCPStatsTracker (the mcp SDK runs sync
tool bodies via anyio.to_thread.run_sync, so this is genuinely
multi-threaded, unlike the async REST routes)
- app/mcp/server.py: instrument search_regulations, add get_mcp_status()
- app/config/settings.py: optional MCP_PUBLIC_URL override, required
because the Vite proxy and reverse proxies rewrite the Host header
- StatusPage.tsx: MCP Server card, joins the existing parallel fetch
Counters are process-local by design; token usage is already persisted
by ModelUsageTracker since MCP calls route through ask().
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
