fix: pin conventionalcommits preset to avoid writer version mismatch

[joris974]

Summary

Release runs on main started failing after #212 with:

Missing helper: "conventional-changelog-conventionalcommits requires conventional-changelog-writer@9 or newer (conventional-changelog@8 or newer). Your changelog tooling loaded an older writer which cannot render this preset. Update the tooling or use an older major version of the preset."

Root cause: .releaserc.yaml uses preset: 'conventionalcommits', and release.yml installs the preset package unpinned via extra_plugins, so it resolves to whatever is latest (conventional-changelog-conventionalcommits@10.4.0 as of this writing). That version added a hard runtime failure when its templates are rendered by conventional-changelog-writer < 9.

cycjimmy/semantic-release-action@v6.0.0 bundles semantic-release@25.0.2, whose @semantic-release/release-notes-generator@14.1.0 depends on conventional-changelog-writer@^8.0.0 — one major behind what the unpinned preset now requires. Hence the mismatch.

Fix

Pin the extra_plugins entry to conventional-changelog-conventionalcommits@^9, the last major line still compatible with conventional-changelog-writer@8.

Verification

Reproduced and fixed locally by installing the action's exact bundled versions and calling @semantic-release/release-notes-generator's generateNotes directly:

• semantic-release@25.0.2 + unpinned conventional-changelog-conventionalcommits → resolves 10.4.0, conventional-changelog-writer stays at 8.4.0 (deduped from release-notes-generator) → reproduces the exact reported error.
• Same setup with conventional-changelog-conventionalcommits@^9 → resolves 9.3.1 against the same conventional-changelog-writer@8.4.0 → generateNotes succeeds and produces correct release notes.

Test plan

• Confirmed root cause and fix locally against the action's pinned dependency versions
• CI passes on this PR
• After merge, verify the next release run on main succeeds