feat(wechat): add Intent Transaction Layer with unified task schema

Introduce Draft → Confirm → Commit flow for WeChat schedule intents behind
feature flags, plus h5_tasks dual-write/read aggregation and rollout scripts
so reminders and automations get explicit user confirmation before persisting.

Co-authored-by: Cursor <cursoragent@cursor.com>

server/portal-integration-services-bootstrap.mjs

@@ -29,6 +29,8 @@ export async function bootstrapPortalIntegrationServices({
   tkmindProxy,
   scheduleService,
   scheduledTaskService = null,
+  intentDraftService = null,
+  taskUnifiedService = null,
   sessionSnapshotService = null,
   wechatScheduleLlmConfigService,
   wechatIntentRouter = null,
@@ -163,6 +165,14 @@ export async function bootstrapPortalIntegrationServices({
         env.H5_SCHEDULE_ENABLED === '1'
           ? scheduledTaskService
           : null,
+      intentDraftService:
+        env.H5_INTENT_TRANSACTION_ENABLED === '1'
+          ? intentDraftService
+          : null,
+      taskUnifiedService:
+        env.H5_UNIFIED_TASKS_ENABLED === '1'
+          ? taskUnifiedService
+          : null,
       wechatScheduleLlmConfigService,
       llmProviderService,
       chatIntentRouter,