Extract and generalize notification dispatch:
- TelegramClient: full Bot API client with photo/video/document/media group support
- TelegramFileCache: TTL and thumbhash-based file_id caching
- WebhookClient: simple JSON POST client
- NotificationQueue: persistent deferred notification queue for quiet hours
- NotificationDispatcher: routes ServiceEvent to targets, renders templates
- StorageBackend protocol + JsonFileBackend for persistence
- TargetConfig dataclass for target configuration
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
alexei.dolgolyov
16a41efec1