Fixes for CI workflow

[CyrilleB79]

Changes

Various CI fixes and improvements:

• Do not try to build / make release if the workflow is run from this add-on template repo, since it fails and the template is not meant to be used as a release. Fixes: Do not restrict workflow triggers to addon path #22 (comment).
• Modernized uv usage with "uv sync", fixing the failure on previously used "uv pip install". Discussed in Do not restrict workflow triggers to addon path #22 (comment).
• Use uv for each command using Python so that the correct environment is used
• Added .egg-info to .git-ignore
• Updated readme

Tests

Testing done in https://github.com/CyrilleB79/AddonTemplateTest/, release V1.0

[CyrilleB79]

@nvdaes, I’d really appreciate your review, especially regarding the use of uv. I’m fairly new to it, so a second check would be valuable.
@josephsl, your review would also be appreciated if you have the bandwidth, though I understand you’ve recently reduced / deprioritized NVDA work.

[nvdaes]

Thanks @CyrilleB79 . I'll review it ASAP, probably tomorrow. Today I am affected by influenza or some kind of virus, but I don't think this is important and probably tomorrow I will be better.

[CyrilleB79]

No problem, feel free to review when you can. Wish you get better soon.

[seanbudd]

@nvdaes - I'm happy to merge as-is, but did you want to check it as well?

[nvdaes]

Thanks @CyrilleB79 and @seanbudd . LGTM