Refactor UpdateManager & Remove UpdateChecker

[Szpoti]

Better to review commit-by-commit.

As the backend gets more and more disconnected from the client, we can refactor the update workflow as well.

This PR aims to remove UpdateChecker and use mainly the UpdateManager (which got refactored as well).
What happens here:

• We get the client version from GitHub mainly, removing another backend dependency.
• This way we only need the BackendMajorVersion from the backend.
• We can get rid of UpdateChecker this way.
• Refactor UpdateManager and check for updates only during initialization.

[lontivero]

It looks very well.

[lontivero]

Why is this?

The whole class should be replaced by something like this:

public record UpdateStatus(bool ClientUpToDate, bool BackendCompatible, bool IsReadyToInstall, Version ClientVersion);

[kiminuo]

I was just about to write the same. It would be a great simplification.

[Szpoti]

We could simplify it yes, but to note:
When we instantiate UpdateStatus here, we aren't aware of ClientVersion (API request needed), ReadyToInstall (download needed) and ClientUpToDate (client version comparison needed).
I went with this because this way we can set these properties in UpdateManager when its needed.

[kiminuo]

Records allow you to set properties:

Or was your question about something else?

[turbolay]

@kiminuo is this ok? 6edb57b

[turbolay]

Something I don't get: Does this PR remove the ability for the client to find updates while it's running? It looks from the code that by removing UpdateChecker we can now only catch updates on relaunch
Can we make UpdateManager a PeriodicRunner (with UpdateClientAsync being ActionAsync)?

[Szpoti]

@turbolay Your suggestion was my original idea, @lontivero suggested to go with this one-time-check solution.

[turbolay]

@lontivero Can you confirm that having the UpdateManager as a PeriodicRunner is a cNACK for you?

I personally dislike the idea of running the check for updates only at launch for a simple reason: It's better to never close Wasabi. It's less true without coinjoining but still. Also I see no harm in having a request per hour to GitHub.

[lontivero]

Your suggestion was my original idea, @lontivero suggested

Yes, it is true, I suggested that. Well, I have no problem with checking from time to time. However I think this PR is good and I would like to merge it. @Szpoti would you like to check periodically again but i a different PR?

[MaxHillebrand]

fwiw, I think checking for releases once a day is enough. If we would check every hour, that's almost 1500 unnecessary checks during a two month release cycle. Distributing the new downloads across 24 hours is also a nice load balancing for the server, and in the case of a swift hotfix some users wouldn't download the initial version.

[Szpoti]

@lontivero I can do that if you find it necessary. It can be a 24 hours cycle as Max suggested it.
Also pls reply your idea about this comment: #13027 (comment)

[turbolay]

tACK

I pushed a commit for suggestion about making UpdateStatus a record. I also fixed conflicts.

I will merge considering we had several reviews and I only changed style (the equality comparer were not custom). If what I did with the record is not what you had in mind @kiminuo please make another PR.

I will make a new PR about PeriodicRunner