feat(root): implement dynamic todo list refresh and UI enhancements

This change adds a mechanism to refresh the todo list dynamically when the underlying service updates, improving UI responsiveness and user experience. It also updates documentation and removes deprecated files.

- New Features:
  - Added `_refresh_todos` method to rebuild the todo list when `get_todo_service().todos` changes.
  - Introduced `TodoListCapture` class for mouse capture handling of the todo list window.
- Enhancements:
  - Updated README with corrected image paths, installation tips, and manual installation commands.
  - Introduced `start.py` to launch the application or lock mode.
  - Removed deprecated `config.json` and `debug_memory.py`.
- Bug Fixes:
  - Fixed lock screen screenshot path in README.

src/services/brightness.py

@@ -0,0 +1,91 @@
+from fabric.core.service import Property, Service, Signal
+from fabric.utils import GLib, exec_shell_command_async, logger, monitor_file, os
+
+
+def exec_brightnessctl_async(args: str):
+    exec_shell_command_async(f"brightnessctl {args}", lambda _: None)
+
+
+# Discover screen backlight device
+try:
+    screen_device = os.listdir("/sys/class/backlight")
+    screen_device = screen_device[0] if screen_device else ""
+except FileNotFoundError:
+    logger.error("No backlight devices found, brightness control disabled")
+    screen_device = ""
+
+
+class Brightness(Service):
+    """Service to manage screen brightness levels."""
+
+    instance = None
+
+    @staticmethod
+    def get_initial():
+        if Brightness.instance is None:
+            Brightness.instance = Brightness()
+
+        return Brightness.instance
+
+    @Signal
+    def screen(self, value: int) -> None:
+        """Signal emitted when screen brightness changes."""
+        # Implement as needed for your application
+
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+
+        # Path for screen backlight control
+        self.screen_backlight_path = f"/sys/class/backlight/{screen_device}"
+
+        # Initialize maximum brightness level
+        self.max_screen = self.do_read_max_brightness(self.screen_backlight_path)
+
+        if screen_device == "":
+            return
+
+        # Monitor screen brightness file
+        self.screen_monitor = monitor_file(f"{self.screen_backlight_path}/brightness")
+
+        self.screen_monitor.connect(
+            "changed",
+            lambda _, file, *args: self.emit(
+                "screen",
+                round(int(file.load_bytes()[0].get_data())),
+            ),
+        )
+
+        # Log the initialization of the service
+        logger.info(f"Brightness service initialized for device: {screen_device}")
+
+    def do_read_max_brightness(self, path: str) -> int:
+        # Reads the maximum brightness value from the specified path.
+        max_brightness_path = os.path.join(path, "max_brightness")
+        if os.path.exists(max_brightness_path):
+            with open(max_brightness_path) as f:
+                return int(f.readline())
+        return -1  # Return -1 if file doesn't exist, indicating an error.
+
+    @Property(int, "read-write")
+    def screen_brightness(self) -> int:
+        # Property to get or set the screen brightness.
+        brightness_path = os.path.join(self.screen_backlight_path, "brightness")
+        if os.path.exists(brightness_path):
+            with open(brightness_path) as f:
+                return int(f.readline())
+        logger.warning(f"Brightness file does not exist: {brightness_path}")
+        return -1  # Return -1 if file doesn't exist, indicating error.
+
+    @screen_brightness.setter
+    def screen_brightness(self, value: int):
+        # Setter for screen brightness property.
+        if not (0 <= value <= self.max_screen):
+            value = max(0, min(value, self.max_screen))
+
+        try:
+            exec_brightnessctl_async(f"--device '{screen_device}' set {value}")
+            self.emit("screen", int((value / self.max_screen) * 100))
+        except GLib.Error as e:
+            logger.error(f"Error setting screen brightness: {e.message}")
+        except Exception as e:
+            logger.exception(f"Unexpected error setting screen brightness: {e}")