Push firecracker to all environments on release

[djeebus]

No description provided.

[cursor]

PR Summary

Medium Risk
Changes the release pipeline control flow and deploy behavior across multiple environments; mistakes could skip needed builds or publish/deploy incomplete artifacts.

Overview
The workflow now always runs build, publish, and deploy, relying on per-arch checks and has_new_artifacts gating instead of a global skip_build, which can still trigger deploy even when nothing new was produced.

Several GitHub Actions references look invalid (actions/checkout@v6, actions/upload-artifact@v7, actions/download-artifact@v8) and will likely break the workflow.

scripts/validate.py drops --github-repo and changes artifact detection to read release assets via gh release view, and tests are rewritten accordingly; this can mis-detect assets if the gh repo context isn’t what you expect.

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[cursor]

Cursor Bugbot has reviewed your changes and found 2 potential issues.

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