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/osd/components/capslock.py

@@ -0,0 +1,50 @@
+from fabric.widgets.label import Label
+from fabric.widgets.svg import Svg
+from fabric.utils import get_relative_path
+from .base import BaseOSDContainer
+from services.capslock import CapsLock
+
+
+class CapsLockOSDContainer(BaseOSDContainer):
+    def __init__(self, window, **kwargs):
+        super().__init__(window, **kwargs)
+        self.capslock = CapsLock.get_initial()
+        self._setup_specific_components()
+        self._connect_specific_signals()
+
+    def _setup_specific_components(self):
+        self.osd_image = Svg(
+            get_relative_path("../../../assets/icons/misc/caps-lock.svg"),
+            size=(100, 100),
+            name="osd-image",
+            h_align="center",
+            v_align="center",
+            h_expand=True,
+            v_expand=True,
+        )
+        self.label = Label(name="osd-label")
+        self.add(self.osd_image)
+        self._update_display(self.capslock.is_on)
+
+    def _connect_specific_signals(self):
+        self.capslock.connect("state_changed", self._on_caps_lock_state_changed)
+
+    def _on_caps_lock_state_changed(self, _, is_on: bool):
+        self._update_display(is_on)
+        self.update()
+
+    def _update_display(self, is_on: bool):
+        icon_path = "caps-lock.svg" if is_on else "caps-lock-off.svg"
+        self.osd_image.set_from_file(
+            get_relative_path(f"../../../assets/icons/misc/{icon_path}")
+        )
+        if is_on:
+            self.add_style_class("capslock-on")
+            self.remove_style_class("capslock-off")
+        else:
+            self.add_style_class("capslock-off")
+            self.remove_style_class("capslock-on")
+
+    def update(self, *_):
+        # We don't need a separate display update here as it's handled in the signal
+        super().update()