feat: add CalDAV synchronization with automatic sync

- Add CaldavService with tsdav/ical.js for CalDAV server communication
- Add CaldavController, CaldavRepository, and caldav routes
- Add client-side CaldavConfigService with sync(), config CRUD
- Add CalDAV settings UI with config load/save in settings screen
- Sync on login, auto-login (AuthGuard), periodic timer (calendar), and sync button
- Push single events to CalDAV on server-side create/update/delete
- Push all events to CalDAV after chat event confirmation
- Refactor ChatService to use EventService instead of direct EventRepository
- Rename CalDav/calDav to Caldav/caldav for consistent naming
- Add Radicale Docker setup for local CalDAV testing
- Update PlantUML diagrams and CLAUDE.md with CalDAV architecture

apps/server/src/controllers/EventController.ts

@@ -1,17 +1,43 @@
 import { Response } from "express";
-import { RecurringDeleteMode } from "@calchat/shared";
+import { CalendarEvent, RecurringDeleteMode } from "@calchat/shared";
 import { EventService } from "../services";
 import { createLogger } from "../logging";
 import { AuthenticatedRequest } from "./AuthMiddleware";
+import { CaldavService } from "../services/CaldavService";
 
 const log = createLogger("EventController");
 
 export class EventController {
-  constructor(private eventService: EventService) {}
+  constructor(
+    private eventService: EventService,
+    private caldavService: CaldavService,
+  ) {}
+
+  private async pushToCaldav(userId: string, event: CalendarEvent) {
+    if (await this.caldavService.getConfig(userId)) {
+      try {
+        await this.caldavService.pushEvent(userId, event);
+      } catch (error) {
+        log.error({ error, userId }, "Error pushing event to CalDAV");
+      }
+    }
+  }
+
+  private async deleteFromCaldav(userId: string, event: CalendarEvent) {
+    if (event.caldavUUID && (await this.caldavService.getConfig(userId))) {
+      try {
+        await this.caldavService.deleteEvent(userId, event.caldavUUID);
+      } catch (error) {
+        log.error({ error, userId }, "Error deleting event from CalDAV");
+      }
+    }
+  }
 
   async create(req: AuthenticatedRequest, res: Response): Promise<void> {
     try {
-      const event = await this.eventService.create(req.user!.userId, req.body);
+      const userId = req.user!.userId;
+      const event = await this.eventService.create(userId, req.body);
+      await this.pushToCaldav(userId, event);
       res.status(201).json(event);
     } catch (error) {
       log.error({ error, userId: req.user?.userId }, "Error creating event");
@@ -83,15 +109,19 @@ export class EventController {
 
   async update(req: AuthenticatedRequest, res: Response): Promise<void> {
     try {
+      const userId = req.user!.userId;
       const event = await this.eventService.update(
         req.params.id,
-        req.user!.userId,
+        userId,
         req.body,
       );
       if (!event) {
         res.status(404).json({ error: "Event not found" });
         return;
       }
+
+      await this.pushToCaldav(userId, event);
+
       res.json(event);
     } catch (error) {
       log.error({ error, eventId: req.params.id }, "Error updating event");
@@ -101,46 +131,44 @@ export class EventController {
 
   async delete(req: AuthenticatedRequest, res: Response): Promise<void> {
     try {
+      const userId = req.user!.userId;
       const { mode, occurrenceDate } = req.query as {
         mode?: RecurringDeleteMode;
         occurrenceDate?: string;
       };
 
+      // Fetch event before deletion to get caldavUUID for sync
+      const event = await this.eventService.getById(req.params.id, userId);
+      if (!event) {
+        res.status(404).json({ error: "Event not found" });
+        return;
+      }
+
       // If mode is specified, use deleteRecurring
       if (mode) {
         const result = await this.eventService.deleteRecurring(
           req.params.id,
-          req.user!.userId,
+          userId,
           mode,
           occurrenceDate,
         );
 
-        // For 'all' mode or when event was completely deleted, return 204
-        if (result === null && mode === "all") {
-          res.status(204).send();
-          return;
-        }
-
-        // For 'single' or 'future' modes, return updated event
+        // Event was updated (single/future mode) - push update to CalDAV
         if (result) {
+          await this.pushToCaldav(userId, result);
           res.json(result);
           return;
         }
 
-        // result is null but mode wasn't 'all' - event not found or was deleted
+        // Event was fully deleted (all mode, or future from first occurrence)
+        await this.deleteFromCaldav(userId, event);
         res.status(204).send();
         return;
       }
 
       // Default behavior: delete completely
-      const deleted = await this.eventService.delete(
-        req.params.id,
-        req.user!.userId,
-      );
-      if (!deleted) {
-        res.status(404).json({ error: "Event not found" });
-        return;
-      }
+      await this.eventService.delete(req.params.id, userId);
+      await this.deleteFromCaldav(userId, event);
       res.status(204).send();
     } catch (error) {
       log.error({ error, eventId: req.params.id }, "Error deleting event");