fix(review): auto-merge reads live mergeable_state (green+approved PRs were stuck open)

src/github/backfill.ts

@@ -1977,9 +1977,22 @@
   }
 
   const ciState: LiveCiAggregate["ciState"] = failingDetails.length > 0 ? "failed" : anyPending ? "pending" : total > 0 ? "passed" : "unverified";
   return { ciState, failingDetails };
 }
 
+/**
+ * Fetch a PR's LIVE `mergeable_state` (clean / dirty / blocked / unstable / behind / has_hooks / unknown). The
+ * STORED value lags GitHub's async recompute — e.g. right after gittensory[bot]'s own APPROVE flips a `blocked`
+ * PR to `clean`, the stored row is still `blocked`, which stops an otherwise-eligible PR from auto-merging
+ * (observed: green+approved PRs stuck OPEN at `mergeState=CLEAN`). The auto-maintain planner uses this so the
+ * merge decision sees the CURRENT state. `unknown` (GitHub still computing) ⇒ caller treats as not-yet-clean and
+ * a later trigger / the sweep retries. Best-effort: a fetch error returns undefined (caller falls back to stored).
+ */
+export async function fetchLivePullRequestMergeState(env: Env, repoFullName: string, prNumber: number, token: string | undefined): Promise<string | undefined> {
+  const result = await githubJsonWithHeaders<{ mergeable_state?: string | null }>(env, repoFullName, `/pulls/${prNumber}`, token).catch(() => undefined);
+  return result?.data.mergeable_state ?? undefined;
+}
+
 async function fetchPullRequestDetailsFromGraphQl(
   env: Env,
   repoFullName: string,

src/queue/processors.ts

@@ -62,9 +62,10 @@
   backfillOpenPullRequestDetails,
   backfillRegisteredRepositories,
   backfillRepositorySegment,
   enqueueRepositoryOpenDataBackfill,
   fetchAndStorePullRequestFilesForReview,
   fetchLiveCiAggregate,
+  fetchLivePullRequestMergeState,
   refreshContributorActivity,
   refreshInstallationHealth,
   refreshPullRequestDetails,
@@ -605,10 +606,13 @@
   // planner uses this to NEVER approve/merge a PR whose CI isn't green, to CLOSE a red-CI non-owner PR (citing
   // the failing checks) / HOLD the owner's, and to DEFER entirely while CI is still pending.
   const ciToken = await createInstallationToken(env, installationId).catch(() => undefined);
-  const [changedFiles, hardGuardrailGlobs, ciAggregate] = await Promise.all([
+  const [changedFiles, hardGuardrailGlobs, ciAggregate, liveMergeState] = await Promise.all([
     resolvePullRequestFilesForReview(env, { installationId, repoFullName, pullNumber: pr.number }),
     loadHardGuardrailGlobs(env, repoFullName),
     fetchLiveCiAggregate(env, repoFullName, pr.headSha, ciToken ?? env.GITHUB_PUBLIC_TOKEN),
+    // Live mergeable_state — the stored one lags GitHub's async recompute after the bot's own approve, which
+    // otherwise leaves a green+approved PR stuck OPEN at mergeState=CLEAN (never auto-merged).
+    fetchLivePullRequestMergeState(env, repoFullName, pr.number, ciToken ?? env.GITHUB_PUBLIC_TOKEN),
   ]);
   const changedPaths = changedFiles.map((file) => file.path).filter((path) => path.length > 0);
   const repoOwner = repoFullName.includes("/") ? repoFullName.slice(0, repoFullName.indexOf("/")) : "";
@@ -629,7 +633,7 @@
     ciState: ciAggregate.ciState,
     failingCheckNames: ciAggregate.failingDetails.map((detail) => detail.name),
     pr: {
-      mergeableState: pr.mergeableState,
+      mergeableState: liveMergeState ?? pr.mergeableState,
       reviewDecision: pr.reviewDecision,
       slopRisk: pr.slopRisk,
       labels: pr.labels,