feat: Add telegram & discord notification

[Lyliya]

I use Telegram to keep track of downloaded content (Sonarr, Radarr, etc...). I though it would be cool to have a notification system when Floatplane Downloaded add new content to my library at the same place.

Pretty basic notification system :

• Add notifications in Settings DB
• Add Telegram notify to send message to corresponding token and chat_id
• Can be extended to other services if needed
• Notify download and error

[Inrixia]

Hrm I'll need to fix why the release workflow is trying to run here but that's passing.

[Inrixia]

Two things. For errors could you please include the error message.

And for discord etc, if it's possible to provide some more info ie using a embed etc that would be ideal. Should have access to the video object so doing stuff like setting the album art etc and title/short desc.

Lmk

[Lyliya]

What about something like that for discord ?
The description field is bloated for some video and make it harder to read.
Would be sick to have the channel profile picture to add to the author