fix(settings): log tool source resolution failures (no silent swallow)

web/mcp_introspection.py

@@ -4,8 +4,11 @@
 from __future__ import annotations
 
 import inspect
+import logging
 from typing import Any
 
+logger = logging.getLogger(__name__)
+
 
 async def list_mcp_tools() -> list[dict[str, Any]]:
     """List all registered MCP tools with metadata."""
@@ -24,8 +27,10 @@ async def list_mcp_tools() -> list[dict[str, Any]]:
                 _, line = inspect.getsourcelines(fn)
                 source_location = f"{file}:{line}"
                 module = fn.__module__
-            except Exception:
-                pass
+            except Exception as e:
+                logger.debug(
+                    "tool_source_resolution_failed name=%s err=%s", t.name, e,
+                )
         out.append({
             "name": t.name,
             "description": t.description or "",