fix: show actual bot names on watch page instead of Black/White fallbacks

The gameState stream event does not carry player names, so snapshot.white/black
were always undefined and the UI fell back to the literal strings "Black" and
"White". Fix by fetching the full game object (GET /api/tournament/{id}/game/{gameId})
on page load, which includes BotRef with real names, and storing them in
dedicated whiteName/blackName fields.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/pages/tournament-watch/tournament-watch.component.html

@@ -2,10 +2,10 @@
   <header class="watch-head">
     <a class="back-link" routerLink="/tournaments">← Tournaments</a>
     <div class="watch-title">
-      @if (snapshot?.white && snapshot?.black) {
-        <span class="player">{{ snapshot!.white!.name }}</span>
+      @if (whiteName && blackName) {
+        <span class="player">{{ whiteName }}</span>
         <span class="vs">vs</span>
-        <span class="player">{{ snapshot!.black!.name }}</span>
+        <span class="player">{{ blackName }}</span>
         @if (snapshot?.round) {
           <span class="round-tag">Round {{ snapshot!.round }}</span>
         }
@@ -24,12 +24,12 @@
   <div class="watch-layout">
     <div class="board-wrap">
       <div class="clock clock-top" [class.active]="status === 'ongoing' && turn === 'black'">
-        <span class="clock-label">{{ snapshot?.black?.name ?? 'Black' }}</span>
+        <span class="clock-label">{{ blackName ?? 'Black' }}</span>
         <span class="clock-time">{{ formatTime(clock?.blackTime) }}</span>
       </div>
       <app-chess-board [fen]="fen"></app-chess-board>
       <div class="clock clock-bot" [class.active]="status === 'ongoing' && turn === 'white'">
-        <span class="clock-label">{{ snapshot?.white?.name ?? 'White' }}</span>
+        <span class="clock-label">{{ whiteName ?? 'White' }}</span>
         <span class="clock-time">{{ formatTime(clock?.whiteTime) }}</span>
       </div>
     </div>