Redesign tvOS player controls with centered transport cluster

- Move Close to a top-right circular icon; bottom row reorganizes into
  left (Settings/Info/Comments), center transport (Previous/PlayPause/Next),
  and right (Queue) clusters with equal side frames so transport stays
  geometrically centered.
- Introduce a circular icon-only `TVTransportButtonStyle` (primary variant
  for Play/Pause) mirroring the new Close button look.
- Always render Previous/Next so Play/Pause position is fixed; dim and
  disable when unavailable.
- Share `isTransportDisabled` on `PlayerState` and reuse it on iOS and
  tvOS; apply it (plus symbol replace transition) to the tvOS Play/Pause
  button.

Yattee/Localizable.xcstrings

@@ -6671,6 +6671,26 @@
         }
       }
     },
+    "player.controls.pause" : {
+      "localizations" : {
+        "en" : {
+          "stringUnit" : {
+            "state" : "translated",
+            "value" : "Pause"
+          }
+        }
+      }
+    },
+    "player.controls.play" : {
+      "localizations" : {
+        "en" : {
+          "stringUnit" : {
+            "state" : "translated",
+            "value" : "Play"
+          }
+        }
+      }
+    },
     "player.controls.quality" : {
       "extractionState" : "stale",
       "localizations" : {