A separate changelog for desktop

### Your use case

#### What would you like to do?
I would like to know what changed only on desktop and not what changes on web which is used by desktop
#### Why would you like to do it?
We have a fork and we build this fork based on versions of Element web/react/js, we don't want to have to go through the commits of desktop to find out what changed there. We also don't want to fish out the changes made for desktop from the changes made for web. We don't want to have to merge desktop every time we merge web, because that is extra work.
#### How would you like to achieve it?
Maybe changes which are merged to master could be documented somewhere when they are merged to master? (would also be nice to know how often this happens...)

### Have you considered any alternatives?

CTRL + F in the element changelogs.

### Additional context

Here are some of these questions asked in the chat.

https://matrix.to/#/!YTvKGNlinIzlkMTVRl:matrix.org/$-UCjblRYexpMvRGvinAgjlXCLELPRweshkytmbVSP_s?via=matrix.org&via=tchncs.de&via=envs.net