feat(scratch): Add test for MPRIS signal emission handling

This test validates that MprisPlayer correctly emits the `seeked` signal with both small and large value ranges, using a mocked DBus helper to avoid runtime DBus dependencies.

- New Features:
  - Add `scratch/test_mpris_fix.py` to test signal emission edge cases.
- Enhancements:
  - None
- Bug Fixes:
  - None

scratch/test_mpris_fix.py

@@ -0,0 +1,56 @@
+import sys
+import os
+
+# Add project root to path
+sys.path.append(os.getcwd())
+
+from services.mpris import MprisPlayer
+
+
+def test_signal_emission():
+    # We need a bus name to initialize MprisPlayer, but we won't actually call DBus methods if we don't trigger them
+    # However, MprisPlayer.__init__ calls do_register which tries to connect to DBus
+    # I'll mock the GioDBusHelper to avoid DBus connection issues
+
+    import utils.dbus_helper
+
+    original_helper = utils.dbus_helper.GioDBusHelper
+
+    class MockDBusHelper:
+        def __init__(self, *args, **kwargs):
+            self.proxy = None
+
+        def call_method(self, *args, **kwargs):
+            pass
+
+        def set_property(self, *args, **kwargs):
+            pass
+
+    utils.dbus_helper.GioDBusHelper = MockDBusHelper
+
+    try:
+        player = MprisPlayer("org.mpris.MediaPlayer2.mock")
+
+        # Test values
+        small_val = 1000
+        large_val = 3000000000  # > 2^31 - 1
+
+        print(f"Testing emission with small value: {small_val}")
+        player.emit("seeked", small_val)
+        print("Success")
+
+        print(f"Testing emission with large value: {large_val}")
+        player.emit("seeked", large_val)
+        print("Success")
+
+    except Exception as e:
+        print(f"Failed: {e}")
+        import traceback
+
+        traceback.print_exc()
+    finally:
+        utils.dbus_helper.GioDBusHelper = original_helper
+
+
+if __name__ == "__main__":
+    test_signal_emission()