* feat: add notification system with Ntfy.sh and Apprise providers (#231)
Add push notification support for mirror job events with two providers:
- Ntfy.sh: direct HTTP POST to ntfy topics with priority/tag support
- Apprise API: aggregator gateway supporting 100+ notification services
Includes database migration (0010), settings UI tab, test endpoint,
auto-save integration, token encryption, and comprehensive tests.
Notifications are fire-and-forget and never block the mirror flow.
* fix: address review findings for notification system
- Fix silent catch in GET handler that returned ciphertext to UI,
causing double-encryption on next save. Now clears token to ""
on decryption failure instead.
- Add Zod schema validation to test notification endpoint, following
project API route pattern guidelines.
- Mark notifyOnNewRepo toggle as "coming soon" with disabled state,
since the backend doesn't yet emit new_repo events. The schema
and type support is in place for when it's implemented.
* fix notification gating and config validation
* trim sync notification details
