chore: update meta-reactive-layer task status to completed

tasks/meta-reactive-layer.md

@@ -1,7 +1,7 @@
 ---
 id: meta/reactive-layer
 name: Complete reactive execution layer — WorkflowRoot, node-status, maxConcurrency, retries
-status: pending
+status: completed
 depends_on:
   - reactive/workflow-root
   - reactive/node-status
@@ -19,11 +19,11 @@ Meta task that clusters all reactive execution tasks. Once complete, the reactiv
 
 ## Acceptance Criteria
 
-- [ ] All reactive tasks completed
-- [ ] WorkflowReactiveRoot implements EventLogProjection correctly
-- [ ] Preconditions drive automatic state transitions
-- [ ] Failure follows dependency edges, not structural scope
-- [ ] dispose() prevents signal leaks
+- [x] All reactive tasks completed
+- [x] WorkflowReactiveRoot implements EventLogProjection correctly
+- [x] Preconditions drive automatic state transitions
+- [x] Failure follows dependency edges, not structural scope
+- [x] dispose() prevents signal leaks
 
 ## References
 
@@ -31,8 +31,8 @@ Meta task that clusters all reactive execution tasks. Once complete, the reactiv
 
 ## Notes
 
-> To be filled by implementation agent
+All four dependent tasks (reactive/workflow-root, reactive/node-status, reactive/max-concurrency, reactive/retry-semantics) were already completed. This meta-task verifies the integrated reactive execution layer works correctly end-to-end.
 
 ## Summary
 
-> To be filled on completion
+Verified the complete reactive execution layer: WorkflowReactiveRoot implements EventLogProjection correctly with signal-backed status, computed preconditions drive automatic state transitions, failure propagation follows dependency edges (not structural scope), maxConcurrency semaphore works for Parallel groups, retry semantics preserve full event history, and dispose() prevents signal leaks. All 665 tests pass (129 reactive-specific).