feat: add Drone CI pipelines, Jest unit tests, and Prettier check

Add Drone CI with server build/test and format check pipelines.
Add unit tests for password utils and recurrenceExpander.
Add check_format script, fix Jest config to ignore dist/,
remove dead CaldavService.test.ts, apply Prettier formatting.

apps/server/src/controllers/EventController.ts

@@ -40,7 +40,10 @@ export class EventController {
       await this.pushToCaldav(userId, event);
       res.status(201).json(event);
     } catch (error) {
-      log.error({ err: error, userId: req.user?.userId }, "Error creating event");
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error creating event",
+      );
       res.status(500).json({ error: "Failed to create event" });
     }
   }
@@ -67,7 +70,10 @@ export class EventController {
       const events = await this.eventService.getAll(req.user!.userId);
       res.json(events);
     } catch (error) {
-      log.error({ err: error, userId: req.user?.userId }, "Error getting events");
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error getting events",
+      );
       res.status(500).json({ error: "Failed to get events" });
     }
   }