feat(radiobrowser): add search, paging and favourite lookup

beefy_player/widgets/help.py

@@ -35,7 +35,7 @@ HELP_ROWS: tuple[tuple[str, str], ...] = (
     ("m", "mute / unmute"),
     ("f", "favourite — favourites float to the top"),
     ("/", "filter stations by title, genre or description"),
-    ("esc", "clear the filter / close overlays"),
+    ("esc", "close the search box; esc again clears the filter"),
     (
         "v",
         "cycle visualiser: mirror → bars → wave → waterfall → radial → braille",