Fix RPG state restoration on message delete and swipe

- Add MESSAGE_DELETED event handler to restore state from last assistant message
- Fix swipe to use previous message's data for LLM context (prevents time/story advancing)
- Update UI to show rolled-back state immediately when triggering new swipe
- Handle edge cases: empty chat, first message swipe, no previous RPG data

index.js

@@ -150,6 +150,7 @@ import {
     onMessageReceived,
     onCharacterChanged,
     onMessageSwiped,
+    onMessageDeleted,
     updatePersonaAvatar,
     clearExtensionPrompts,
     onGenerationEnded,
@@ -1175,6 +1176,7 @@ jQuery(async () => {
                 [event_types.GENERATION_ENDED]: onGenerationEnded,
                 [event_types.CHAT_CHANGED]: [onCharacterChanged, updatePersonaAvatar, restoreCheckpointOnLoad, clearSessionAvatarPrompts],
                 [event_types.MESSAGE_SWIPED]: onMessageSwiped,
+                [event_types.MESSAGE_DELETED]: onMessageDeleted,
                 [event_types.USER_MESSAGE_RENDERED]: updatePersonaAvatar,
                 [event_types.SETTINGS_UPDATED]: updatePersonaAvatar
             });