feat(tournaments): remove external server add/remove UI

Servers are now env-var configured; the Servers dialog, add form,
remove buttons, and TournamentServerService are all deleted.

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

src/app/pages/tournaments/tournaments.component.ts

@@ -71,11 +71,6 @@ export class TournamentsComponent implements OnInit {
   showServersDialog = false;
   servers: ExternalTournamentServer[] = [];
   serversLoading = false;
-  newServerLabel = '';
-  newServerUrl = '';
-  addingServer = false;
-  addServerError: string | null = null;
-  removingServerId: string | null = null;
 
   ngOnInit(): void {
     this.authService.currentUser$
@@ -248,9 +243,6 @@ export class TournamentsComponent implements OnInit {
   }
 
   openServersDialog(): void {
-    this.newServerLabel = '';
-    this.newServerUrl = '';
-    this.addServerError = null;
     this.showServersDialog = true;
     this.serversLoading = true;
     this.tournamentServerService.list()
@@ -265,40 +257,6 @@ export class TournamentsComponent implements OnInit {
     this.showServersDialog = false;
   }
 
-  addServer(): void {
-    const label = this.newServerLabel.trim();
-    const url = this.newServerUrl.trim();
-    if (!label || !url || this.addingServer) return;
-    this.addingServer = true;
-    this.addServerError = null;
-    this.tournamentServerService.register(label, url).subscribe({
-      next: server => {
-        this.addingServer = false;
-        this.servers = [...this.servers, server];
-        this.newServerLabel = '';
-        this.newServerUrl = '';
-        this.loadTournaments();
-      },
-      error: err => {
-        this.addingServer = false;
-        this.addServerError = err.error?.error ?? 'Failed to add server.';
-      }
-    });
-  }
-
-  removeServer(id: string): void {
-    if (this.removingServerId) return;
-    this.removingServerId = id;
-    this.tournamentServerService.remove(id).subscribe({
-      next: () => {
-        this.removingServerId = null;
-        this.servers = this.servers.filter(s => s.id !== id);
-        this.loadTournaments();
-      },
-      error: () => { this.removingServerId = null; }
-    });
-  }
-
   private loadTournaments(): void {
     this.tournamentService.list()
       .pipe(takeUntilDestroyed(this.destroyRef))