refactor: one self-contained folder per platform service

Each platform/apps/<service>/ now holds its own application.yaml
(multi-source: chart + values + raw-manifest extras), values.yaml, and
any extra manifests (HTTPRoute, RBAC, ClusterSecretStore) together,
replacing the split apps/*.yaml + manifests/*/ + separate *-config
Application pattern.

Root platform-app.yaml now recurses platform/apps/*/application.yaml
only. Extras get a resource-level sync-wave (1) so they still land
after their service's Helm chart within the same Application sync.

Also adds an HTTPRoute for vault (vault.fireflylab.local) - exposed
same as every other service here, accepted as LAN-only exposure.

platform/apps/headlamp/rbac.yaml

@@ -0,0 +1,22 @@
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: headlamp-admin
+  namespace: headlamp
+  annotations:
+    argocd.argoproj.io/sync-wave: "1"
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: headlamp-admin
+  annotations:
+    argocd.argoproj.io/sync-wave: "1"
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: cluster-admin
+subjects:
+  - kind: ServiceAccount
+    name: headlamp-admin
+    namespace: headlamp