fix: harden paired runtime turn coordination

src/message-runtime-queue.ts

@@ -15,6 +15,7 @@ import {
   resolveCursorKeyForRole,
   resolveQueuedTurnRole,
 } from './message-runtime-rules.js';
+import { claimPairedTurnExecution } from './paired-follow-up-scheduler.js';
 import type {
   ExecuteTurnFn,
   RoleToChannelMap,
@@ -23,9 +24,30 @@ import type {
   Channel,
   NewMessage,
   PairedTask,
+  PairedTurnReservationIntentKind,
   RegisteredGroup,
 } from './types.js';
 
+function resolveQueuedTurnReservationIntent(args: {
+  task: PairedTask;
+  turnRole: 'owner' | 'reviewer' | 'arbiter';
+  hasHumanMessage: boolean;
+}): PairedTurnReservationIntentKind {
+  if (args.turnRole === 'reviewer') {
+    return 'reviewer-turn';
+  }
+  if (args.turnRole === 'arbiter') {
+    return 'arbiter-turn';
+  }
+  if (args.hasHumanMessage) {
+    return 'owner-turn';
+  }
+  if (args.task.status === 'merge_ready') {
+    return 'finalize-owner-turn';
+  }
+  return 'owner-follow-up';
+}
+
 export async function runPendingPairedTurnIfNeeded(args: {
   chatJid: string;
   group: RegisteredGroup;
@@ -79,6 +101,29 @@ export async function runPendingPairedTurnIfNeeded(args: {
     return null;
   }
 
+  if (pendingTurn.channel) {
+    const claimedUpdatedAt = claimPairedTurnExecution({
+      chatJid,
+      runId: args.runId,
+      task,
+      intentKind: pendingTurn.intentKind,
+    });
+    if (!claimedUpdatedAt) {
+      args.log.info(
+        {
+          chatJid,
+          taskId: task.id,
+          taskStatus: task.status,
+          taskUpdatedAt: task.updated_at,
+          intentKind: pendingTurn.intentKind,
+        },
+        'Skipped paired pending turn because the task revision was already claimed elsewhere',
+      );
+      return true;
+    }
+    task.updated_at = claimedUpdatedAt;
+  }
+
   return executePendingPairedTurn({
     pendingTurn,
     chatJid,
@@ -176,6 +221,34 @@ export async function runQueuedGroupTurn(args: {
     return false;
   }
 
+  if (task) {
+    const intentKind = resolveQueuedTurnReservationIntent({
+      task,
+      turnRole,
+      hasHumanMessage: hasHumanMsg,
+    });
+    const claimedUpdatedAt = claimPairedTurnExecution({
+      chatJid,
+      runId,
+      task,
+      intentKind,
+    });
+    if (!claimedUpdatedAt) {
+      log.info(
+        {
+          taskId: task.id,
+          taskStatus,
+          taskUpdatedAt: task.updated_at,
+          intentKind,
+          turnRole,
+        },
+        'Skipped queued paired turn because the task revision was already claimed elsewhere',
+      );
+      return true;
+    }
+    task.updated_at = claimedUpdatedAt;
+  }
+
   if (endSeq !== null) {
     advanceLastAgentCursor(
       args.lastAgentTimestamps,