[Feature Request] Support for multiple Sonarr instances

[Yankees4life]

Hello there

I think there should be support for multiple Sonarr Intances. I have 3 Sonarr Instances on hand (Anime, Shows, 4K Shows) so I don't want to spin up 3 versions of Episeerr in order to use this.

[Vansmak]

Looked into this properly. It's not just a matter of pointing webhooks from both instances at Episeerr — two things would need to change:

1. Series ID collision: series state is keyed only by Sonarr's own internal series_id (a bare integer). Sonarr assigns IDs independently per instance, so instance A's series 5 and instance B's series 5 are very likely different shows — rule assignment, watch/activity state, and the pending-deletion queue would silently collide and overwrite each other under the same ID.
2. Outbound calls only ever target one Sonarr: SONARR_URL/SONARR_API_KEY are single global values set once at startup, not per-instance. So even with webhooks wired up correctly from both, every outbound call Episeerr makes (monitor, search, delete episode file, fetch episodes) goes to whichever one Sonarr is configured in Setup — a second instance's episodes can't actually be managed at all right now.

So real multi-instance support needs per-instance URL/key storage plus a compound key (instance_id + series_id) everywhere series state is stored — a legitimate feature, not something achievable via config today. Leaving this open as a real gap rather than closing it.