ci: add automatic nightly builds to the Github Actions workflow

[uznog]

Named after and hopefully resolving #1382

Changes include:

• workflow running at a cron schedule (12:00 AM / 00:00 UTC)
• workflow scheduled by cron runs nightly job, generating a pre-release

Nightly build name is yazi-nightly-<timestamp>. Flow tested with dummy artifact created:
https://github.com/uznog/yazi/actions/runs/10215675482

And here's the resulting pre-release: https://github.com/uznog/yazi/releases/tag/yazi-nightly-20240802-1236

[uncenter]

If I'm reading this right, this creates a new nightly release every day? I think creating a single nightly-tagged rolling release might be better 🤔 , though I might not be understanding exactly what this is trying to solve.

[uznog]

I totally agree. I pushed a commit changing tag name to be a static nightly, which will work as the latest version built off master branch every day

[sxyazi]

Thanks for the PR!

Could you also add a build time to the release body? Something like:

From commit: d2ebadb
Generated on: 2024-08-04 23:00:00 UTC

[uznog]

I guess this does the job:
https://github.com/uznog/yazi/releases/tag/nightly

[uncenter]

Looks great!

[sxyazi]

Thanks!