fix: queue on-create jobs sequentially and fix history ordering

runJobsOnCreate now awaits each job before starting the next,
ensuring they don't stomp each other's DB writes in parallel.

getInstanceHistory changed to ORDER BY changed_at ASC, id ASC so
the creation event (lowest id) is always first regardless of
same-second timestamps.

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

server/db.js

@@ -227,7 +227,7 @@ export function importInstances(rows, historyRows = []) {
 
 export function getInstanceHistory(vmid) {
   return db.prepare(
-    'SELECT * FROM instance_history WHERE vmid = ? ORDER BY changed_at DESC'
+    'SELECT * FROM instance_history WHERE vmid = ? ORDER BY changed_at ASC, id ASC'
   ).all(vmid);
 }