feat(candy-survival): toggle-and-walk knock mode, unified animations, score rewards, RPC fix

- Changed knock from instant-ambush to toggle-and-walk: press Q to toggle Knock Mode ON, walk into target to execute, consumed on use
- Unified knock animation with other game modes (attack_mode SFX, bump, 3-tile knockback, stagger)
- Added +100 score rewards for completing goals, KNOCK, and GHOST
- Fixed RPC unknown peer ID crash for AI bots in ghost/candy stack sync
- Bots auto-toggle is_charged_strike when they have knock charges
- Fixed profile panel username update on connected peers
- Added SafeNakamaMultiplayerBridge for match state crash prevention

scripts/ui/profile_panel.gd

@@ -607,7 +607,7 @@ func _on_save_name_pressed() -> void:
 		emit_signal("profile_updated")
 		await get_tree().create_timer(3.0).timeout
 		status_label.text = ""
-	else:
+	elif status_label.text == "Saving...":
 		_set_status("Failed to update name.", Color.RED)
 
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