fix(quick-260610-i4x-01): replace node-cron schedule() with setInterval in three broker workers

- poller.ts: setInterval(cb, 5 * 60 * 1000) replaces schedule('*/5 * * * *', cb)
- outboxWorker.ts: setInterval(cb, 15 * 1000) replaces schedule('*/15 * * * * *', cb)
- reminderScheduler.ts: setInterval(cb, 60 * 1000) replaces schedule('* * * * *', cb)
- Remove 'import { schedule } from node-cron' from all three files
- Update doc comments to reflect setInterval and document why (node-cron 4.2.1 silent skip)
- Callback bodies and .catch wrappers unchanged; typecheck clean; 91/91 broker tests pass

apps/api/src/broker/outboxWorker.ts

@@ -17,13 +17,12 @@
  * T-03-14: create-before-delete ordering; create-fail aborts delete.
  *
  * runOutboxDrain is exported for unit testing.
- * startOutboxWorker wraps it in a 15-second node-cron schedule.
+ * startOutboxWorker wraps it in a 15-second setInterval.
+ * (node-cron 4.2.1 silently skipped scheduled executions in the long-running server process;
+ * setInterval fires reliably in the same process — replaced to fix the silent skip.)
  *
  * Source: poller.ts pattern (runPoll/startBrokerPoller)
- * Source: https://github.com/node-cron/node-cron (v4 stable)
  */
-
-import { schedule } from 'node-cron'
 import { z } from 'zod'
 import { and, eq, lte } from 'drizzle-orm'
 import { db } from '../db/client.js'
@@ -752,11 +751,13 @@ export async function runOutboxDrain(): Promise<void> {
 /**
  * Starts the 15-second background outbox drain schedule.
  * Call once at API startup (wired in index.ts beside startBrokerPoller).
+ * Uses setInterval instead of node-cron: node-cron 4.2.1 silently skipped executions
+ * in the long-running server process; setInterval fires reliably.
  */
 export function startOutboxWorker(): void {
-  schedule('*/15 * * * * *', () => {
+  setInterval(() => {
     runOutboxDrain().catch((err: unknown) => {
       console.error('[outboxWorker] Unhandled runOutboxDrain error:', err)
     })
-  })
+  }, 15 * 1000)
 }