fix: skip release workflow when triggered by its own merge

The release workflow re-triggers on main when its own PR merges,
causing `make rc` to fail with "nothing to commit" since docs are
already up to date. Skip the generate/PR steps when the push commit
is a release commit, and make the Makefile commit conditional as a
defensive fallback.

Co-Authored-By: Claude <svc-devxp-claude@slack-corp.com>

Author: zimeg

.github/workflows/release.yml

@@ -90,7 +90,7 @@ jobs:
           echo "Bumping $LATEST_TAG to v$NEXT_VERSION"
 
       - name: Generate release commit
-        if: steps.version.outputs.has_changes == 'true'
+        if: steps.version.outputs.has_changes == 'true' && !startsWith(github.event.head_commit.message, 'chore: release slack-cli')
         env:
           RELEASE_VERSION: ${{ steps.version.outputs.next }}
         run: |
@@ -100,7 +100,7 @@ jobs:
           git push origin "HEAD:refs/heads/rc" --force
 
       - name: Create or update release PR
-        if: steps.version.outputs.has_changes == 'true'
+        if: steps.version.outputs.has_changes == 'true' && !startsWith(github.event.head_commit.message, 'chore: release slack-cli')
         env:
           GH_TOKEN: ${{ steps.credentials.outputs.token }}
           RELEASE_VERSION: ${{ steps.version.outputs.next }}

Makefile

@@ -102,4 +102,4 @@ rc:
 	git add docs/guides/installing-the-slack-cli-for-mac-and-linux.md
 	git add docs/guides/installing-the-slack-cli-for-windows.md
 	@printf "$(FONT_BOLD)Git Commit$(FONT_RESET)\n"
-	git commit -m "chore: release slack-cli v$(RELEASE_VERSION)"
+	git diff --cached --quiet || git commit -m "chore: release slack-cli v$(RELEASE_VERSION)"