Fix issues with fetching updates of Unity versions by using the new Api

[Legi428]

Hey! :)

This is my first pull request so I'm not sure if I did everything correctly. I'd be happy to adjust any comments you might have.

So this pull request changes a few things. I'll try to summarize them here:

• Rewrite GetUnityUpdates to use the new Api.
• The rewrite respects the usage limit (10 requests per second)
• I added model classes for the big api fetch to make the system a bit more robust
• This change introduced the usage of System.Text.Json though
• I included a cached version of the current full list
• This cached version is updated whenever the program fetches a version not yet seen
• I added a new filter for Tech releases (There's an enum in the Api fetch for Tech, LTS, Alpha, Beta so I figured I just add that)
• The radio buttons are now a StackPanel which makes it easier for them to be spaced evenly as well as position anywhere

I removed a bunch of code that has gotten redundand or wasn't used anymore.

[unitycoder]

thanks! i'll have a look

[unitycoder]

Testing it for few days, just to get a feel for it : )

One modification could be nice: for downloads, can still grab the assistant (even though its not listed on unity releases API) https://download.unity3d.com/download_unity/4dae1bb8668d/UnityDownloadAssistant-2022.3.49f1.exe

That makes installing easier, while it still works (as they are planning to remove it). So when user clicks download buttons, it would try to download assistant, if not available, then have to download that editor installer: https://download.unity3d.com/download_unity/4dae1bb8668d/Windows64EditorInstaller/UnitySetup64-2022.3.49f1.exe

notes:

• Download and install button hangs (probably since its downloading that bigger installer)

[Legi428]

Testing it for few days, just to get a feel for it : )

One modification could be nice: for downloads, can still grab the assistant (even though its not listed on unity releases API) https://download.unity3d.com/download_unity/4dae1bb8668d/UnityDownloadAssistant-2022.3.49f1.exe

That makes installing easier, while it still works (as they are planning to remove it). So when user clicks download buttons, it would try to download assistant, if not available, then have to download that editor installer: https://download.unity3d.com/download_unity/4dae1bb8668d/Windows64EditorInstaller/UnitySetup64-2022.3.49f1.exe

notes:

* Download and install button hangs (probably since its downloading that bigger installer)

Thank you for your quick reply and looking at it! :) I have added a progress window that also allows the user to cancel any downloads that take too long and it also doesn't make the program appear frozen. I've attached a screenshot of what it looks like. I tried to make it use the styling that is already present. I also made it so that the download assistant is downloaded by default and the big download is only a fallback.

[unitycoder]

thanks for the updates, ill keep using it for a while again!

[unitycoder]

Looks good to me, i'll merge it soon!

[Legi428]

That's great, thank you for the suggestions. They made it really nice to use. I'm glad you like my changes. Cheers!

[unitycoder]

thanks!