feat(serr_sync): adds Seerr sync configuration

This commit introduces the ability to configure Seerr sync settings directly within the service management interface.

- Integrates Seerr sync functionality with a new panel in the service details page
- Allows configuration of external primary and subordinate instances
- Provides options to control which types of requests are synced (pending, approved, declined, deletions)
- Displays sync status, failed requests, and instance roles
- Implements data loading and saving of Seerr sync settings

Author: I-am-PUID-0