Fix weapons not working on client: remove is_predicting check + init loadout

- Removed the is_predicting() early-return in weapon_manager._rollback_tick
  which blocked all weapon actions on the client (player owned by server)
- Added client-side weapon loadout initialization in player-spawner._spawn
  so the player has weapons immediately, before server state sync arrives
- Server reconciles via rollback state sync

Movement was fixed in v0.2.2 (window focus grab). This addresses
the remaining 'can't switch or use weapons' issue.

examples/multiplayer-fps/scripts/player-spawner.gd

@@ -173,6 +173,15 @@ func _spawn(id: int):
 	if rollback_sync and rollback_sync.has_method("process_settings"):
 		rollback_sync.process_settings()
 
+	# On the client side, initialize weapon loadout locally so the player
+	# has weapons immediately. The server will reconcile via rollback state sync.
+	if not multiplayer.is_server():
+		var weapon_mgr = avatar.find_child("WeaponManager")
+		if weapon_mgr and weapon_mgr.has_method("set_default_loadout"):
+			# Default to T team — server will correct via state sync
+			weapon_mgr.set_default_loadout(1)  # TeamManager.Team.T = 1
+			print("[Spawner] Client-side weapon loadout initialized for peer %s" % id)
+
 func get_team_spawn_point(peer_id: int, spawn_idx: int = 0) -> Vector3:
 	var team := team_manager.get_team(peer_id)
 	var points: Array[Marker3D]