fix(gateway): fail fast exec approvals when no approvers are reachable

Co-authored-by: fanxian831-netizen <262880470+fanxian831-netizen@users.noreply.github.com>

src/gateway/exec-approval-manager.ts

@@ -86,18 +86,7 @@ export class ExecApprovalManager {
       promise,
     };
     entry.timer = setTimeout(() => {
-      // Update snapshot fields before resolving (mirror resolve()'s bookkeeping)
-      record.resolvedAtMs = Date.now();
-      record.decision = undefined;
-      record.resolvedBy = null;
-      resolvePromise(null);
-      // Keep entry briefly for in-flight awaitDecision calls
-      setTimeout(() => {
-        // Compare against captured entry instance, not re-fetched from map
-        if (this.pending.get(record.id) === entry) {
-          this.pending.delete(record.id);
-        }
-      }, RESOLVED_ENTRY_GRACE_MS);
+      this.expire(record.id);
     }, timeoutMs);
     this.pending.set(record.id, entry);
     return promise;
@@ -138,6 +127,27 @@ export class ExecApprovalManager {
     return true;
   }
 
+  expire(recordId: string, resolvedBy?: string | null): boolean {
+    const pending = this.pending.get(recordId);
+    if (!pending) {
+      return false;
+    }
+    if (pending.record.resolvedAtMs !== undefined) {
+      return false;
+    }
+    clearTimeout(pending.timer);
+    pending.record.resolvedAtMs = Date.now();
+    pending.record.decision = undefined;
+    pending.record.resolvedBy = resolvedBy ?? null;
+    pending.resolve(null);
+    setTimeout(() => {
+      if (this.pending.get(recordId) === pending) {
+        this.pending.delete(recordId);
+      }
+    }, RESOLVED_ENTRY_GRACE_MS);
+    return true;
+  }
+
   getSnapshot(recordId: string): ExecApprovalRecord | null {
     const entry = this.pending.get(recordId);
     return entry?.record ?? null;