refactor(modules): improve exception handling and simplify service usage

Enhancements
- Replace bare `except:` with `except Exception:` in multiple modules- Cast step calculation to `int` for consistent type
- Simplify `get_battery_icon_file` to return a string directly
- Use `get_todo_service()` instead of module-level `todo_service` throughout todo widget
- Remove unused `"zen": "zen-browser"` mapping entry

Bug Fixes
- Prevent bare exception swallowing by catching `Exception` explicitly
- Ensure proper cleanup of timer IDs and other resources
- Delete unused modules/osdd components

New Features
- None

modules/desktop/widget.py

@@ -546,7 +546,7 @@ class CpuInfo(SystemInfoBase):
                             for p in ["package id 0", "core 0", ""]
                         ):
                             return round(entry.current, 1)
-        except:
+        except Exception:
             pass
         return None