ci: skip duplicate codecane staging tags

Author: brandonkachen

.github/workflows/cli-release-staging.yml

@@ -17,6 +17,7 @@ jobs:
     if: contains(github.event.pull_request.title, '[codecane]')
     outputs:
       new_version: ${{ steps.bump_version.outputs.new_version }}
+      tag_exists: ${{ steps.check_tag.outputs.exists }}
     steps:
       - uses: actions/checkout@v4
         with:
@@ -117,11 +118,28 @@ jobs:
           🤖 Generated with Codebuff
           Co-Authored-By: Codebuff <noreply@codebuff.com>"
 
+      - name: Check if staging tag exists
+        id: check_tag
+        run: |
+          TAG="v${{ steps.bump_version.outputs.new_version }}"
+          if git ls-remote --tags origin "$TAG" | grep -q "$TAG"; then
+            echo "Tag $TAG already exists on origin; skipping tag creation."
+            echo "exists=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "exists=false" >> "$GITHUB_OUTPUT"
+          fi
+
       - name: Create and push staging tag
+        if: steps.check_tag.outputs.exists != 'true'
         run: |
           git tag "v${{ steps.bump_version.outputs.new_version }}"
           git push origin "v${{ steps.bump_version.outputs.new_version }}"
 
+      - name: Tag already exists
+        if: steps.check_tag.outputs.exists == 'true'
+        run: |
+          echo "Tag v${{ steps.bump_version.outputs.new_version }} already present on origin; continuing without pushing."
+
       - name: Upload staging metadata
         uses: actions/upload-artifact@v4
         with:
@@ -189,6 +207,14 @@ jobs:
         env:
           VERSION: ${{ needs.prepare-and-commit-staging.outputs.new_version }}
         run: |
+          EXISTING_RELEASE=$(curl -s -H "Authorization: token ${{ secrets.CODEBUFF_GITHUB_TOKEN }}" \
+            "https://api.github.com/repos/CodebuffAI/codebuff/releases/tags/v${VERSION}")
+
+          if echo "$EXISTING_RELEASE" | jq -e '.id' >/dev/null 2>&1; then
+            echo "Release for v${VERSION} already exists; skipping creation."
+            exit 0
+          fi
+
           CURRENT_TIME=$(date -u +"%Y-%m-%dT%H:%M:%SZ")
           RELEASE_BODY=$(cat <<'EOF'
           ## Codecane v${VERSION} (Staging)
@@ -266,7 +292,20 @@ jobs:
           node-version: 20
           registry-url: https://registry.npmjs.org/
 
+      - name: Check if version already published
+        id: check_npm
+        env:
+          VERSION: ${{ needs.prepare-and-commit-staging.outputs.new_version }}
+        run: |
+          if npm view codecane@"$VERSION" version >/dev/null 2>&1; then
+            echo "codecane@$VERSION already published to npm; skipping publish."
+            echo "published=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "published=false" >> "$GITHUB_OUTPUT"
+          fi
+
       - name: Publish codecane staging package to npm
+        if: steps.check_npm.outputs.published != 'true'
         run: |
           cd cli/release-staging
           npm publish --access public