feat: UX improvements — secure webhooks, locale fixes, dynamic languages, UI polish

- Remove top paginator from dashboard events, keep only bottom
- Fix test message locale: pass UI locale to email/matrix bot tests
- Convert webhook auth mode from text input to icon grid selector
- Generate secure UUID tokens for webhook URLs instead of sequential IDs
- Move Recent Payloads into per-provider expandable container (lazy-loaded)
- Make template config languages dynamic via app settings instead of hardcoded
- Change default dev port to 5175

packages/server/src/notify_bridge_server/config.py

@@ -33,7 +33,7 @@ class Settings(BaseSettings):
 
     telegram_webhook_secret: str = ""
 
-    cors_allowed_origins: str = "http://localhost:5173"
+    cors_allowed_origins: str = "http://localhost:5175"
     """Comma-separated allowed origins for CORS (e.g. 'http://localhost:5173,https://myapp.com')."""
 
     static_dir: str = ""