[BUG] Resolver - Anything preventing an update to download may leave you with a broken project

[owlboy]

Describe the bug When the Resolver starts to update a package, it appears the first thing it does is delete the old one. This is bad when something goes wrong with downloading an update. It's especially troublesome if its the VRCSDK or other core components.

To Reproduce Steps to reproduce the behavior:

1. Block access to the URL a package update is hosted on. (to simulate issues reaching it)
2. Use Resolver to update the package.
3. Observe that the Resolver may be stuck in a broken state and the package you were updating is now missing from your project.

Expected behavior Improved error handling/anticipation.

Desktop (please complete the following information):

• OS: macOS
• Version 12.6

Additional context This was discovered when the 404 error/caching issues were occurring. See #226 issuecomment-1493256771

If previously used packages are cached (I'm not sure if that occurs), they may need to be cleared to allow for repro in some cases.

[VRC-INYO]

This bug is annoying especially for players who are live at country with national firewall, likely 100% chance to get broken project after update. :o

[orels1]

VCC 2.2.x should now roll the package back when encountering an issue instead of leaving the project without a package if it was already removed