fix(notifications): a notice value is no plain string, so a translated name cannot freeze in one language

A name goes in as raw(), a translated word as its own msg(): tsc now lists every value, and the
ones that froze are said when shown — Watch later and an untitled channel in the pin and channel
notices, a Plex season's name in its removal toast (a new seasonTitleText, which seasonTitle says).

frontend/src/i18n/locales/en/plex.json

@@ -344,6 +344,7 @@
     "playShow": "Play the show",
     "playSeason": "Play the season",
     "removeFromPlaylist": "Remove from the playlist",
+    "seasonOfShow": "{{show}} · {{season}}",
     "removedToast": "“{{title}}” removed from the playlist",
     "undoRemoveFailed": "Couldn't put it back in the playlist"
   },

frontend/src/i18n/locales/hu/plex.json

@@ -344,6 +344,7 @@
     "playShow": "Sorozat lejátszása",
     "playSeason": "Évad lejátszása",
     "removeFromPlaylist": "Eltávolítás a listáról",
+    "seasonOfShow": "{{show}} · {{season}}",
     "removedToast": "„{{title}}” eltávolítva a listáról",
     "undoRemoveFailed": "Nem sikerült visszatenni a listára"
   },