Semver check derives what callers used to declare: first release, tag prefix, changelog and measured set

The checker reads each package's tag prefix, changelog and assemblies directory
from scripts/release-packages.mjs and derives the release record from git tags.
A first release is the absence of any older tag in a checkout that holds other
tags; a malformed same-prefix tag, a checkout without tags and an unreadable
repository refuse. The measured set is every managed assembly (CLI header in
the PE bytes) tracked at the previous tag at any depth; an unbuilt one is a
break, a built assembly with no namesake is an addition.

Deleted with their branches, refusals and tests: --first-release, --api-new,
--tag-prefix, --changelog, --api-baseline-path and the workflow first-release
decision line. Any unknown option is now a usage error.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

.github/workflows/publish-packages.yml

@@ -75,17 +75,7 @@ jobs:
         if: startsWith(github.ref, 'refs/tags/cultcache-ts-v')
         run: |
           tagged="${GITHUB_REF_NAME#cultcache-ts-v}"
-          # The package's first release carries --first-release. The checker believes it only
-          # when no other cultcache-ts tag exists, so this test only avoids refusing the
-          # releases that follow; it does not decide anything.
-          first=""
-          if [ -z "$(git tag -l 'cultcache-ts-v*' | grep -vxF "$GITHUB_REF_NAME" || true)" ]; then first="--first-release"; fi
-          node scripts/check-changelog-semver.mjs \
-            --package "@gamecult/cultcache-ts" \
-            --changelog packages/cultcache-ts/CHANGELOG.md \
-            --version "$tagged" \
-            --tag-prefix cultcache-ts \
-            $first
+          node scripts/check-changelog-semver.mjs --package "@gamecult/cultcache-ts" --version "$tagged"
 
       - name: Build and test
         working-directory: packages/cultcache-ts
@@ -165,15 +155,7 @@ jobs:
         if: steps.selected.outputs.run == 'true' && startsWith(github.ref, 'refs/tags/')
         run: |
           tagged="${GITHUB_REF_NAME#${{ matrix.package }}-v}"
-          # See the cultcache-ts job: the checker, not this test, decides whether a first release is real.
-          first=""
-          if [ -z "$(git tag -l '${{ matrix.package }}-v*' | grep -vxF "$GITHUB_REF_NAME" || true)" ]; then first="--first-release"; fi
-          node scripts/check-changelog-semver.mjs \
-            --package "${{ matrix.package }}" \
-            --changelog packages/${{ matrix.package }}/CHANGELOG.md \
-            --version "$tagged" \
-            --tag-prefix "${{ matrix.package }}" \
-            $first
+          node scripts/check-changelog-semver.mjs --package "${{ matrix.package }}" --version "$tagged"
 
       # Lower layers install from source so a release of one package is tested
       # against the sibling revision it was cut with, not whatever PyPI has.