ci: stabilize Release workflow PR creation by replacing gh pr create with REST API flow (#137)

Author: Copilot

.github/workflows/release.yml

@@ -72,21 +72,31 @@ jobs:
               # Push the branch
               git push origin $BRANCH_NAME
               
-              # Create PR using GitHub CLI
-              gh pr create \
-                --title "chore(release): ${VERSION}" \
-                --body "Automated release PR for version ${VERSION}
+              PR_TITLE="chore(release): ${VERSION}"
+              PR_BODY="Automated release PR for version ${VERSION}
 
               This PR contains:
               - Updated package.json version
               - Updated yarn.lock (if changed)
               - Updated CHANGELOG.md
 
-              Please review and merge to complete the release process." \
-                --head $BRANCH_NAME \
-                --base master
-              
-              echo "Created PR for release ${VERSION}"
+              Please review and merge to complete the release process."
+
+              EXISTING_PR_URL=$(gh api "repos/${{ github.repository }}/pulls?head=${{ github.repository_owner }}:${BRANCH_NAME}&base=master&state=open" --jq '.[0].html_url // empty')
+
+              if [[ -n "$EXISTING_PR_URL" ]]; then
+                echo "Release PR already exists: ${EXISTING_PR_URL}"
+              else
+                gh api \
+                  --method POST \
+                  "repos/${{ github.repository }}/pulls" \
+                  -f title="$PR_TITLE" \
+                  -f body="$PR_BODY" \
+                  -f head="$BRANCH_NAME" \
+                  -f base="master" \
+                  --jq '.html_url'
+                echo "Created PR for release ${VERSION}"
+              fi
             else
               echo "No changes to commit after staging files"
               git checkout master