fix: ensure release failure comments are posted to PR

The comment job was not running when release failed because it checked
for 'released == true' which is never set on failure.

Changes:
- Changed condition from 'needs.release.outputs.released == true' to
  'needs.release.result != skipped'
- Added default empty value for VERSION in failure comment
- Used bash parameter expansion to conditionally add 'v' prefix

This ensures PR comments are posted for both success and failure cases.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: azu

.github/workflows/release.yml

@@ -130,7 +130,7 @@ jobs:
     if: |
       always() &&
       github.event_name == 'pull_request' &&
-      needs.release.outputs.released == 'true'
+      needs.release.result != 'skipped'
     runs-on: ubuntu-latest
     permissions:
       pull-requests: write
@@ -158,14 +158,14 @@ jobs:
         run: |
           gh pr comment "$PR_NUMBER" \
             --repo "$REPOSITORY" \
-            --body "❌ **Release v$VERSION failed**
+            --body "❌ **Release ${VERSION:+v}$VERSION failed**
 
           Please check the workflow logs for details.
           🔗 Workflow run: $SERVER_URL/$REPOSITORY/actions/runs/$RUN_ID"
         env:
           GH_TOKEN: ${{ github.token }}
           PR_NUMBER: ${{ github.event.pull_request.number }}
-          VERSION: ${{ needs.release.outputs.version }}
+          VERSION: ${{ needs.release.outputs.version || '' }}
           SERVER_URL: ${{ github.server_url }}
           REPOSITORY: ${{ github.repository }}
           RUN_ID: ${{ github.run_id }}