Fix GoReleaser immutable release error with draft-then-publish workflow

[Copilot]

GitHub releases become immutable once published, causing "Cannot upload assets to an immutable release" errors when GoReleaser attempts to upload artifacts to already-published releases.

Changes

• .goreleaser.yaml: Implemented draft-then-publish workflow

  • Changed draft: false → draft: true to create mutable draft releases
  • Removed mode: replace (not needed for drafts)
  • Added make_latest: true to mark as latest when published

• .github/workflows/release.yml: Added automatic draft publishing

  • New workflow step to automatically publish draft releases after artifact upload
  • Uses gh release edit with proper security and robustness

• RELEASE.md: Added comprehensive release process documentation

  • Tag creation and version management (semver)
  • Automated draft-then-publish workflow behavior (triggered on v* tags)
  • Troubleshooting failed releases and re-running releases
  • Pre-release testing with rc tags
  • Notes on draft vs published release mutability

How It Works

1. Tag pushed → workflow triggered
2. GoReleaser creates draft release (mutable)
3. All artifacts uploaded to draft
4. Workflow automatically publishes the draft release
5. Published release becomes immutable (but artifacts are already uploaded)

Configuration Changes

# .goreleaser.yaml
release:
  github:
    owner: ericsuh
    name: adapt
- draft: false
+ draft: true
  prerelease: auto
- mode: replace
+ make_latest: true

# .github/workflows/release.yml
- name: Publish draft release
  env:
    GH_TOKEN: ${{ github.token }}
  run: |
    gh release edit "${{ github.ref_name }}" --draft=false --repo="${{ github.repository }}"

This prevents the "Cannot upload assets to an immutable release" error while maintaining full automation.

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[ericsuh]

This is the actual error thrown in the release:

2026-01-22T22:11:55.0045250Z �[1;94m    •�[m �[1mscm releases�[m
2026-01-22T22:11:55.0047288Z �[1;94m      •�[m releasing                                    �[1;94mtag�[m=v0.1.1 �[1;94mrepo�[m=ericsuh/adapt
2026-01-22T22:11:55.8141986Z �[1;94m      •�[m created                                      �[1;94murl�[m=https://github.com/ericsuh/adapt/releases/tag/v0.1.1
2026-01-22T22:11:55.8147252Z �[1;94m      •�[m uploading to release                         �[1;94mfile�[m=dist/adapt_0.1.1-checksums.txt �[1;94mname�[m=adapt_0.1.1-checksums.txt
2026-01-22T22:11:55.8149875Z �[1;94m      •�[m uploading to release                         �[1;94mfile�[m=dist/adapt_0.1.1_linux_x86_64.tar.gz �[1;94mname�[m=adapt_0.1.1_linux_x86_64.tar.gz
2026-01-22T22:11:55.8154324Z �[1;94m      •�[m uploading to release                         �[1;94mfile�[m=dist/adapt_0.1.1_linux_arm64.tar.gz �[1;94mname�[m=adapt_0.1.1_linux_arm64.tar.gz
2026-01-22T22:11:56.2717336Z �[1;93m      •�[m upload failed                                �[1;93mrequest-id�[m=D818:3F9555:3A3C18:47033B:6972A0AB �[1;93merror�[m=POST https://uploads.github.com/repos/ericsuh/adapt/releases/279179884/assets?name=adapt_0.1.1_linux_arm64.tar.gz: 422 Cannot upload assets to an immutable release. [] �[1;93mname�[m=adapt_0.1.1_linux_arm64.tar.gz �[1;93mrelease-id�[m=279179884
2026-01-22T22:11:56.2886907Z �[1;93m      •�[m upload failed                                �[1;93mrequest-id�[m=D818:3F9555:3A3C14:470336:6972A0AB �[1;93merror�[m=POST https://uploads.github.com/repos/ericsuh/adapt/releases/279179884/assets?name=adapt_0.1.1_linux_x86_64.tar.gz: 422 Cannot upload assets to an immutable release. [] �[1;93mname�[m=adapt_0.1.1_linux_x86_64.tar.gz �[1;93mrelease-id�[m=279179884
2026-01-22T22:11:56.3190482Z �[1;93m      •�[m upload failed                                �[1;93mrequest-id�[m=D818:3F9555:3A3C14:470335:6972A0AB �[1;93merror�[m=POST https://uploads.github.com/repos/ericsuh/adapt/releases/279179884/assets?name=adapt_0.1.1-checksums.txt: 422 Cannot upload assets to an immutable release. [] �[1;93mname�[m=adapt_0.1.1-checksums.txt �[1;93mrelease-id�[m=279179884
2026-01-22T22:11:56.3195383Z �[1;91m  ⨯�[m release failed after 43s                         �[1;91merror�[m=scm releases: failed to publish artifacts: failed to upload adapt_0.1.1_linux_arm64.tar.gz: POST https://uploads.github.com/repos/ericsuh/adapt/releases/279179884/assets?name=adapt_0.1.1_linux_arm64.tar.gz: 422 Cannot upload assets to an immutable release. []
2026-01-22T22:11:56.3254159Z ##[error]The process '/opt/hostedtoolcache/goreleaser-action/2.13.3/x64/goreleaser' failed with exit code 1

[ericsuh]

Try a different fix. I suspect what we need to do is to create releases in draft mode, then add artifacts, then publish. But to do so, we will need to ensure that the Github Action triggers the release, rather than the reverse.

[Copilot]

This is the actual error thrown in the release:

Fixed in commit d2043eb. The solution creates releases as drafts (which are mutable), uploads all artifacts, then automatically publishes the draft. This avoids the "Cannot upload assets to an immutable release" error.

Try a different fix. I suspect what we need to do is to create releases in draft mode, then add artifacts, then publish. But to do so, we will need to ensure that the Github Action triggers the releas...

Implemented in commit d2043eb. GoReleaser now creates draft releases, uploads artifacts to the mutable draft, and then the workflow automatically publishes it using gh release edit --draft=false.