Fix release workflow

[mtmk]

The release workflow triggered on push to main, so any merged PR that changed version.txt would push packages to NuGet. Switch to the release: published event so publishing requires a maintainer to create a GitHub release, and validate the tag matches version.txt before packing. Pass NUGET_API_KEY via env to avoid direct shell interpolation.

[synadia-claude-reviewer]

Claude finished @mtmk's task in 2m 7s —— View job

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PR Review: Fix release workflow

• Read PR diff and workflow file
• Review for correctness and security
• Post inline comments if needed
• Post overall summary

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Overall Assessment

The changes are correct and a clear security improvement. No bugs introduced.

What works well:

• Switching to release: published correctly gates publishing behind an explicit maintainer action. The old push: branches: [main] trigger meant any merged PR touching version.txt could fire a NuGet push.
• contents: read is the right permission now that the tag-creation step is gone.
• Moving NUGET_API_KEY to the env: block is strictly better — secrets containing shell-special characters (e.g. !) can silently misbehave when interpolated directly into run: commands via ${{ }}.
• The validation logic is correct: for release: published, GITHUB_REF_NAME is the tag name (e.g. v1.0.0), ${tag#v} strips the leading v, and the comparison against version.txt via head -n 1 is sound.
• Removing the conditional if: ${{ fromJSON(steps.tag.outputs.create) }} guards simplifies the workflow without loss of safety — the trigger change ensures this only runs when a release is deliberately published, and --skip-duplicate handles any edge case of re-publishing.

One thing to be aware of (pre-existing, not introduced here):

src/Directory.Build.props sets the NuGet package version using:

<Version>$([System.IO.File]::ReadAllText("$(MSBuildProjectDirectory)/version.txt"))</Version>

ReadAllText does not trim. If version.txt ever gains a trailing newline, the packed version could have embedded whitespace. The shell validation uses head -n 1 which strips it, so the tag comparison would pass while the packed version string differs. This is worth guarding against — e.g. $([System.IO.File]::ReadAllText(...).Trim()) — but it's out of scope for this PR.

No issues with the PR as written. LGTM.