Review jobsync: add to services-check and homepage (#291)

## Summary
- Add jobsync pod check (ringtail k3s) and HTTP endpoint to `services-check`
- Add JobSync entry to homepage dashboard under new "Apps" group
- Mark jobsync as reviewed at v1.1.4 (current with upstream)
- Changelog fragment added

## Deployment and Testing
- [ ] Sync homepage app from branch: `argocd app set homepage --revision review/jobsync && argocd app sync homepage`
- [ ] Verify JobSync appears on go.ops.eblu.me dashboard
- [ ] Run `mise run services-check` to verify new checks pass
- [ ] After merge: `argocd app set homepage --revision main && argocd app sync homepage`

Reviewed-on: #291

service-versions.yaml

@@ -157,7 +157,7 @@ services:
 
   - name: jobsync
     type: argocd
-    last-reviewed: null
+    last-reviewed: 2026-03-11
     current-version: "1.1.4"
     upstream-source: https://github.com/Gsync/jobsync/releases
     notes: Job application tracker; nix container on ringtail k3s