feat: reconexión de sesión + 6 nuevas categorías + corrección de bugs

- Añade sistema de reconexión tras refresh/cierre del navegador
  - Persistencia de sesión en localStorage (3h TTL)
  - Banner de reconexión en Home
  - Evento rejoin_room en backend

- Nuevas categorías: Series TV, Marvel/DC, Disney, Memes, Pokémon, Mitología

- Correcciones de bugs:
  - Fix: juego bloqueado al fallar robo (steal decision)
  - Fix: jugador duplicado al cambiar de equipo
  - Fix: rotación incorrecta de turno tras fallo

- Config: soporte para Cloudflare tunnel (allowedHosts)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/services/game_manager.py

@@ -141,9 +141,17 @@ class GameManager:
 
             else:
                 # Original team failed - enable steal
+                failed_team = room["current_team"]
                 room["can_steal"] = True
+
+                # Advance failed team's player index (they had their turn)
+                team_players = room["teams"][failed_team]
+                room["current_player_index"][failed_team] = (
+                    room["current_player_index"][failed_team] + 1
+                ) % len(team_players)
+
                 # Switch to other team for potential steal
-                room["current_team"] = "B" if room["current_team"] == "A" else "A"
+                room["current_team"] = "B" if failed_team == "A" else "A"
 
         # Check if game is over (all questions answered)
         all_answered = all(