Wire campaign scheduler into server boot

tests/campaign-scheduler.test.mjs

@@ -0,0 +1,12 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { openDb } from '../src/db.mjs';
+import { startCampaignScheduler } from '../src/outreach/campaign-scheduler.mjs';
+
+test('startCampaignScheduler retorna funcao de parada que limpa os timers sem lancar erro', () => {
+  const db = openDb(':memory:');
+  const stop = startCampaignScheduler({ db, log: () => {} });
+  assert.equal(typeof stop, 'function');
+  assert.doesNotThrow(() => stop());
+  db.close();
+});