feat(speedtest): worker + hourly cron + history/run routes

Adds speedtest pg-boss worker with injectable runner for testing, hourly
cron enqueue, and /api/speedtest/history (GET) + /run (POST, owner-only) routes.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/cron/index.js

@@ -1,6 +1,7 @@
 import cron from 'node-cron';
 import { runSync } from './sync_source_docs.js';
 import { log } from '../log.js';
+import { enqueue } from '../jobs/queue.js';
 
 export function startCron() {
   // Daily at 03:00 local time
@@ -12,5 +13,12 @@ export function startCron() {
       log.error({ err: e }, 'cron sync.source_doc failed');
     }
   });
+
+  // Hourly speedtest
+  cron.schedule('0 * * * *', async () => {
+    try { await enqueue('speedtest', {}); log.info('cron speedtest enqueued'); }
+    catch (e) { log.error({ err: e }, 'cron speedtest failed'); }
+  });
+
   log.info('cron started');
 }