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/launcher/plugins/password.py

@@ -497,7 +497,7 @@ class PasswordPlugin(PluginBase):
                             f"Password '{name}' {action_word} successfully",
                         ]
                     )
-                except:
+                except Exception:
                     pass
             else:
                 print(f"Failed to add password '{name}'")
@@ -524,7 +524,7 @@ class PasswordPlugin(PluginBase):
                             f"Password '{name}' removed successfully",
                         ]
                     )
-                except:
+                except Exception:
                     pass
             else:
                 print(f"Failed to remove password '{name}'")
@@ -564,7 +564,7 @@ class PasswordPlugin(PluginBase):
                             f"Password for '{name}' copied to clipboard",
                         ]
                     )
-                except:
+                except Exception:
                     pass
 
                 # Clear cache to force refresh