feat: auto-revive in-review tasks with failed pre-merge workflow steps

Adds a SelfHealingManager scan that finds tasks parked in in-review with
a failed pre-merge workflow step and no active session, and sends them
back through the existing sendTaskBackForFix flow (PROMPT.md injection,
step reset, todo → in-progress). Bounded by a new maxPostReviewFixes
setting (default 1) and a per-task postReviewFixCount so a persistently-
failing verifier cannot ping-pong a task indefinitely.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/engine/src/runtimes/in-process-runtime.ts

@@ -575,6 +575,7 @@ export class InProcessRuntime
       this.selfHealingManager = new SelfHealingManager(this.taskStore, {
         rootDir: this.config.workingDirectory,
         recoverCompletedTask: (task) => this.executor.recoverCompletedTask(task),
+        recoverFailedPreMergeStep: (task) => this.executor.recoverFailedPreMergeWorkflowStep(task),
         getExecutingTaskIds: () => this.executor.getExecutingTaskIds(),
         recoverApprovedTriageTask: (task) => this.triageProcessor?.recoverApprovedTask(task) ?? Promise.resolve(false),
         getSpecifyingTaskIds: () => this.triageProcessor?.getProcessingTaskIds() ?? new Set<string>(),