fix(argocd): multisource patch doc, Ingress grafana-onelab

- Root cause: live Application kept spec.source; Argo ignored observability chart
- Add jsonpatch-multisource.json + argocd/README.md migration steps
- Grafana: disable subchart ingress; add templates/ingress-grafana-onelab.yaml

Made-with: Cursor

gitops/docs/BOOTSTRAP.md

@@ -52,4 +52,6 @@ Secret `onelab-rabbit-tls` must exist before RabbitMQ starts (created once from
 
 `gitops/argocd/application.yaml` uses **`spec.sources`** (two Helm charts in one Application). Use **Argo CD 2.6 or newer**.
 
+If the `onelab` Application was created earlier with **`spec.source` only**, Argo will **not** show the observability resources until you remove `source` and set `sources` (a plain `kubectl apply` often leaves the old field). Use [`gitops/argocd/jsonpatch-multisource.json`](../argocd/jsonpatch-multisource.json) as documented in [`gitops/argocd/README.md`](../argocd/README.md).
+
 The second source installs Loki/Promtail/Grafana from `gitops/observability/` (`releaseName: onelab-obs`). Set a strong **`grafana.adminPassword`** in `gitops/observability/values.yaml` before production. Details: [OBSERVABILITY.md](OBSERVABILITY.md).