fix: replace 59 bare except clauses with proper logging (#25)

All `except Exception:` now catch as `except Exception as exc:` with
appropriate logging (warning for critical paths, debug for graceful degradation).

Added logger setup to 4 files that lacked it:
- src/timmy/memory/vector_store.py
- src/dashboard/middleware/csrf.py
- src/dashboard/middleware/security_headers.py
- src/spark/memory.py

31 files changed across timmy core, dashboard, infrastructure, integrations.
Zero bare excepts remain. 1340 tests passing.

src/infrastructure/error_capture.py

@@ -87,7 +87,8 @@ def _get_git_context() -> dict:
         ).stdout.strip()
 
         return {"branch": branch, "commit": commit}
-    except Exception:
+    except Exception as exc:
+        logger.warning("Git info capture error: %s", exc)
         return {"branch": "unknown", "commit": "unknown"}
 
 
@@ -199,7 +200,8 @@ def capture_error(
                     "title": title[:100],
                 },
             )
-        except Exception:
+        except Exception as exc:
+            logger.warning("Bug report screenshot error: %s", exc)
             pass
 
     except Exception as task_exc:
@@ -214,7 +216,8 @@ def capture_error(
             message=f"{type(exc).__name__} in {source}: {str(exc)[:80]}",
             category="system",
         )
-    except Exception:
+    except Exception as exc:
+        logger.warning("Bug report notification error: %s", exc)
         pass
 
     # 4. Record in session logger
@@ -226,7 +229,8 @@ def capture_error(
             error=f"{type(exc).__name__}: {str(exc)}",
             context=source,
         )
-    except Exception:
+    except Exception as exc:
+        logger.warning("Bug report session logging error: %s", exc)
         pass
 
     return task_id