[FEAT]: Read ServApp changelog from Cosmos

[gschurck]

Feature Description

I would like an easy way to follow the changelog of my self hosted apps, to check if there are breaking changes or new features.

What I suggest is that we add a way to see the changelog of a Cosmos Market ServApp we installed. And hopefully, changelog is often written in Github release description for most projects.

The steps would be :

• Set a Github/Gitlab projet url for each market app
• When accessing changelog, fetch stable release descriptions with the API
• Render it as markdown
• Add an option to display only the releases that are useful, like the ones that were released after the last time we read the changelog (so that even users with auto update can keep track of changes easily)

[gschurck]

Also there is the option to use Mark as read like on Coolify to remove a notification element