feat: support multiple event proposals in single AI response

- Change proposedChange to proposedChanges array in ChatMessage type
- Add unique id and individual respondedAction to each ProposedEventChange
- Implement arrow navigation UI for multiple proposals with "Event X von Y" counter
- Add updateProposalResponse() method for per-proposal confirm/reject tracking
- GPTAdapter now collects multiple tool call results into proposals array
- Add RRULE documentation to system prompt (separate events for different times)
- Fix RRULE parsing to strip RRULE: prefix if present
- Add log summarization for large args (conversationHistory, existingEvents)
- Keep proposedChanges logged in full for debugging AI issues

apps/server/src/controllers/ChatController.ts

@@ -31,7 +31,8 @@ export class ChatController {
     try {
       const userId = req.user!.userId;
       const { conversationId, messageId } = req.params;
-      const { action, event, eventId, updates } = req.body as {
+      const { proposalId, action, event, eventId, updates } = req.body as {
+        proposalId: string;
         action: EventAction;
         event?: CreateEventDTO;
         eventId?: string;
@@ -41,6 +42,7 @@ export class ChatController {
         userId,
         conversationId,
         messageId,
+        proposalId,
         action,
         event,
         eventId,
@@ -57,10 +59,12 @@ export class ChatController {
     try {
       const userId = req.user!.userId;
       const { conversationId, messageId } = req.params;
+      const { proposalId } = req.body as { proposalId: string };
       const response = await this.chatService.rejectEvent(
         userId,
         conversationId,
         messageId,
+        proposalId,
       );
       res.json(response);
     } catch (error) {