fix(flatpak): use appid as MPRIS dbus name, remove own-name permission

Change dbus_name from "qbz" to "com.blitzfc.qbz" so the MPRIS name
matches the appid pattern. This eliminates the need for the explicit
--own-name permission as Flatpak allows apps to own names under their
appid namespace automatically.

cc

packaging/flatpak/com.blitzfc.qbz.yml

@@ -40,9 +40,6 @@ finish-args:
   - --talk-name=org.freedesktop.portal.FileChooser
   - --talk-name=org.mpris.MediaPlayer2.*
 
-  # Own MPRIS name to register as media player
-  - --own-name=org.mpris.MediaPlayer2.qbz
-
   # OAuth browser authentication
   - --talk-name=org.freedesktop.portal.OpenURI