Improve Discord RPC

[nexpid]

Cleans up the Discord RPC and makes the timestamp/timer accurate to the currently playing track.

Some notes:

• this is the first time I've worked with flutter/dart, please feel free to critique and/or fix some of my code
• discord has recently added activity types to Discord RPC, so it would be nice if you could add that to https://github.com/KRTirtho/frb_plugins/tree/main/packages/flutter_discord_rpc :)

2024-08-08.23-07-50.mp4

Current RPC for comparison:

[xhyrom]

LGTM, i can work on the activity types tomorrow ;)

[KRTirtho]

It works great. Awesome work ❤️

But there are some unrelated changes that were submitted. Also there's a merge conflict Can you please fix these?

[KRTirtho]

Please remove the unrelated changes. We only need the discord_provider.dart's changes.

[nexpid]

Please remove the unrelated changes. We only need the discord_provider.dart's changes.

The current win32 dependency is outdated and building on Windows machines does not work unless it's updated, that's why I updated all deps

[nexpid]

Please also review @xhyrom's KRTirtho/frb_plugins#1 PR, so I can add its activity type feature to this PR

[KRTirtho]

You should add that in a separate PR. I'll merge this PR now as it is working and link it to appropriate issues

[KRTirtho]

Actually, that's a really small change, I can add it by myself. Thanks for your PR!