chore: remove merge-pr workflow (#2930)

.github/workflows/merge-pr.yml

-name: Merge PR when ready
-
-on:
-  workflow_run:
-    workflows: ["CI"]
-    types:
-      - completed
-
-env:
-  # Allowed authors for auto-merge (update in one place)
-  ALLOWED_MERGE_AUTHORS: wwwillchen,wwwillchen-bot,dyadbot
-
-jobs:
-  merge:
-    # Only run if:
-    # 1. The CI workflow succeeded
-    # 2. The trigger was a pull request (not a push to main)
-    if: >
-      github.event.workflow_run.conclusion == 'success' &&
-      github.event.workflow_run.event == 'pull_request'
-    runs-on: ubuntu-latest
-    permissions:
-      contents: write
-      pull-requests: write
-      actions: read
-    steps:
-      - name: Check PR and merge if ready
-        uses: actions/github-script@v7
-        env:
-          ALLOWED_AUTHORS: ${{ env.ALLOWED_MERGE_AUTHORS }}
-        with:
-          script: |
-            const owner = context.repo.owner;
-            const repo = context.repo.repo;
-            const headSha = context.payload.workflow_run.head_sha;
-            const ciCheckSuiteId = context.payload.workflow_run.check_suite_id;
-
-            console.log(`Checking PR for head SHA: ${headSha}`);
-
-            // Use pull_requests from workflow_run event payload directly
-            // This avoids the 100 PR limit issue when listing all open PRs
-            const workflowRunPRs = context.payload.workflow_run.pull_requests;
-
-            let pr;
-            if (workflowRunPRs && workflowRunPRs.length > 0) {
-              if (workflowRunPRs.length > 1) {
-                console.log(`Multiple PRs (${workflowRunPRs.length}) associated with workflow run — refusing to merge to avoid ambiguity`);
-                return;
-              }
-              const prNumber = workflowRunPRs[0].number;
-              const { data: prData } = await github.rest.pulls.get({
-                owner,
-                repo,
-                pull_number: prNumber,
-              });
-              pr = prData.state === 'open' ? prData : undefined;
-            } else {
-              // Fallback: use listPullRequestsAssociatedWithCommit for targeted lookup
-              // Note: workflow_run.pull_requests is empty for fork PRs
-              const { data: prs } = await github.rest.repos.listPullRequestsAssociatedWithCommit({
-                owner,
-                repo,
-                commit_sha: headSha,
-              });
-              const headBranch = context.payload.workflow_run.head_branch;
-              const openPrs = prs.filter(p => p.state === 'open' && p.head.ref === headBranch);
-              if (openPrs.length > 1) {
-                console.log(`Multiple open PRs found for SHA ${headSha} on branch ${headBranch} — refusing to merge to avoid ambiguity`);
-                return;
-              }
-              pr = openPrs[0];
-            }
-
-            if (!pr) {
-              console.log('No open PR found for this SHA');
-              return;
-            }
-
-            console.log(`Found PR #${pr.number}: ${pr.title}`);
-            console.log(`Author: ${pr.user.login}`);
-
-            // Check if author is allowed (read from environment variable)
-            const allowedAuthors = (process.env.ALLOWED_AUTHORS || '').split(',').map(a => a.trim()).filter(Boolean);
-            if (!allowedAuthors.includes(pr.user.login)) {
-              console.log(`Author ${pr.user.login} is not in allowed list: ${allowedAuthors.join(', ')}`);
-              return;
-            }
-
-            // Check if PR has the "merge-when-ready" label
-            const labels = pr.labels.map(l => l.name);
-            console.log(`PR labels: ${labels.join(', ') || '(none)'}`);
-
-            if (!labels.includes('merge-when-ready')) {
-              console.log('PR does not have "merge-when-ready" label');
-              return;
-            }
-
-            // Verify all check suites have passed
-            const allCheckSuites = await github.paginate(
-              github.rest.checks.listSuitesForRef,
-              { owner, repo, ref: headSha, per_page: 100 },
-              (response) => response.data
-            );
-
-            const pendingOrFailed = allCheckSuites.filter(suite => {
-              // Skip neutral conclusions (e.g., skipped workflows)
-              if (suite.conclusion === 'neutral' || suite.conclusion === 'skipped' || suite.conclusion === 'cancelled') {
-                console.log(`Skipping suite with conclusion '${suite.conclusion}': ${suite.app?.name || 'Unknown'}`);
-                return false;
-              }
-              // Exclude the CI workflow's check suite (already completed successfully — it triggered this workflow)
-              if (suite.id === ciCheckSuiteId) {
-                console.log(`Skipping CI check suite (id=${suite.id})`);
-                return false;
-              }
-              // Skip check suites that are in-progress (conclusion is null)
-              // These are likely workflow_run-triggered workflows that started after CI
-              if (suite.status === 'in_progress' || suite.status === 'queued') {
-                // Check if this is a workflow_run triggered suite by comparing timestamps
-                const ciCompletedAt = new Date(context.payload.workflow_run.updated_at);
-                const suiteCreatedAt = new Date(suite.created_at);
-                if (suiteCreatedAt >= ciCompletedAt) {
-                  console.log(`Skipping workflow_run-triggered suite: ${suite.app?.name || 'Unknown'} (created after CI completed)`);
-                  return false;
-                }
-              }
-              // Check if still in progress or failed
-              return suite.status !== 'completed' || suite.conclusion !== 'success';
-            });
-
-            // Guard: require at least one completed successful check suite
-            const successfulSuites = allCheckSuites.filter(
-              suite => suite.status === 'completed' && suite.conclusion === 'success'
-            );
-            if (successfulSuites.length === 0) {
-              console.log('No completed successful check suites found — refusing to merge');
-              return;
-            }
-
-            if (pendingOrFailed.length > 0) {
-              console.log('Some check suites are still pending or have failed:');
-              pendingOrFailed.forEach(suite => {
-                console.log(`  - ${suite.app?.name || 'Unknown'}: status=${suite.status}, conclusion=${suite.conclusion}`);
-              });
-              return;
-            }
-
-            console.log('All checks passed! Merging PR...');
-
-            // Merge the PR via squash, using sha parameter to prevent TOCTOU race condition
-            try {
-              await github.rest.pulls.merge({
-                owner,
-                repo,
-                pull_number: pr.number,
-                merge_method: 'squash',
-                sha: headSha,
-              });
-              console.log(`Successfully merged PR #${pr.number}`);
-            } catch (error) {
-              console.log(`Failed to merge PR: ${error.message}`);
-              throw error;
-            }