reduce cron schedule from hourly to twice daily

Cuts GitHub Actions runs from ~720/month to ~60, fixing storage quota exhaustion on the free plan.

Made-with: Cursor

Author: ofershap

.github/workflows/cron.yml

@@ -2,7 +2,7 @@ name: Scheduled collection
 
 on:
   schedule:
-    - cron: "0 * * * *"
+    - cron: "0 6,18 * * *"
   workflow_dispatch:
 
 jobs: