feat: add spectator mode for all games

resources/lang/en.json

@@ -227,10 +227,12 @@
     "player": "Player",
     "players": "Players",
     "join_lobby": "Join Lobby",
+    "join_as_spectator": "Join as Spectator",
     "checking": "Checking lobby...",
     "not_found": "Lobby not found. Please check the ID and try again.",
     "error": "An error occurred. Please try again or contact support.",
     "joined_waiting": "Joined successfully! Waiting for game to start...",
+    "joined_as_spectator": "Joined as spectator! You will be able to view the match.",
     "version_mismatch": "This game was created with a different version. Cannot join."
   },
   "public_lobby": {
@@ -284,6 +286,8 @@
     "assigned_teams": "Assigned Teams",
     "empty_teams": "Empty Teams",
     "empty_team": "Empty",
+    "remove_player": "Remove {{username}}",
+    "spectators_count": "{count} spectator(s) watching"
     "remove_player": "Remove {username}"
   },
   "team_colors": {
@@ -555,7 +559,9 @@
     "warships": "Warships",
     "cities": "Cities",
     "show_control": "Show Control",
-    "show_units": "Show Units"
+    "show_units": "Show Units",
+    "spectator": "spectator watching",
+    "spectators": "spectators watching"
   },
   "player_info_overlay": {
     "type": "Type",

src/client/ClientGameRunner.ts

@@ -58,6 +58,7 @@ export interface LobbyConfig {
   clientID: ClientID;
   gameID: GameID;
   token: string;
+  isSpectator?: boolean;
   // GameStartInfo only exists when playing a singleplayer game.
   gameStartInfo?: GameStartInfo;
   // GameRecord exists when replaying an archived game.