chore: add warnings to silent except Exception blocks (#3212)

* log(app): add warnings to silent except Exception blocks

- Internal tool auth header failure now logs a warning instead of
  silently passing, making auth bypass easier to spot in logs.
- Token last_used_at update failure now logs at DEBUG (fire-and-forget,
  non-critical, but useful when debugging token tracking issues).
- Image ownership verification failure now logs a warning so unexpected
  access-check errors surface instead of silently allowing the request.

* log(chat_routes): add warnings to silent except Exception blocks

- clear_orphaned_session_endpoint: log before rollback so failures
  appear in traces when users see stale/deleted model options.
- _endpoint_has_model (JSON parse): log malformed cached_models instead
  of silently treating endpoint as valid.
- _has_any_visible_model (JSON parse): log malformed cached_models
  instead of silently returning empty list.
- timezone header parse: log failure so time-zone-related tool bugs
  (wrong scheduled times, calendar events) are traceable.
- attachments JSON parse: log failure so silently-dropped attachments
  are visible in server logs.

* log(email_routes): add warnings to silent except Exception blocks

- Email alias resolution failure now logs a warning instead of silently
  returning an empty list, making broken account configs diagnosable.

* log(document_routes): add warnings to silent except Exception blocks

- Export ZIP request body parse failure now logs a warning so empty
  exports caused by malformed requests are diagnosable.
- clear_active_document failure on detach now logs a warning to help
  trace doc re-injection bugs like #1160.

* log(agent_loop): add warnings to silent except Exception blocks

- builtin tool overrides load failure now logs a warning so misconfigured
  settings don't silently fall back to defaults without a trace.
- Timezone context injection failure now logs a warning to help debug
  incorrect scheduled times in agent-created tasks.
- PDF form-backed document detection failure now logs a warning so
  broken form-doc UI is traceable to the root cause.

* log(llm_core): add warnings to silent except Exception blocks

- Malformed URL in _is_ollama_native_url now logs a warning so bad
  endpoint configs are traceable instead of silently returning False.
- Model list fetch failure now logs a warning with the endpoint URL so
  endpoints that silently vanish from the model picker are diagnosable.

* log: pass exception via exc_info instead of string interpolation

* fix(logging): avoid logging raw URLs in llm_core error paths

Drop the raw url/base_chat_url from the Ollama-detection and
model-list-fetch warning logs added by this sweep, since these values
can contain private hostnames, internal IPs, credentials, or other
deployment details.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

routes/chat_routes.py

@@ -126,7 +126,8 @@ def _clear_orphaned_session_endpoint(sess, owner: str | None = None) -> bool:
         sess.model = ""
         sess.headers = {}
         return True
-    except Exception:
+    except Exception as e:
+        logger.warning("Failed to clear orphaned session endpoint", exc_info=e)
         db.rollback()
         return False
     finally:
@@ -144,7 +145,8 @@ def _endpoint_cache_contains_model(endpoint, model: str) -> bool:
         return True
     try:
         models = json.loads(raw) if isinstance(raw, str) else raw
-    except Exception:
+    except Exception as e:
+        logger.warning("Failed to parse cached models list, treating as containing model", exc_info=e)
         return True
     if not isinstance(models, list) or not models:
         return True
@@ -236,7 +238,8 @@ def _recover_empty_session_model(sess, session_id: str, owner: str | None = None
                 is_chatgpt_subscription = False
         try:
             cached = json.loads(ep.cached_models) if isinstance(ep.cached_models, str) else (ep.cached_models or [])
-        except Exception:
+        except Exception as e:
+            logger.warning("Failed to parse cached_models for endpoint %r", getattr(ep, "id", "?"), exc_info=e)
             cached = []
         if not cached:
             visible = []
@@ -646,8 +649,8 @@ def setup_chat_routes(
         elif attachments:
             try:
                 att_ids = [str(x) for x in json.loads(attachments)]
-            except Exception:
-                pass
+            except Exception as e:
+                logger.warning("Failed to parse attachments JSON, ignoring attachments", exc_info=e)
 
         no_memory = str(form_data.get("no_memory", "")).lower() == "true"
         pre_context_tool_policy = build_effective_tool_policy(