feat: split artifactapi config into conf.d and update to v2.7.1 (#92)

Split monolithic remotes.yaml into per-type-package files under
resources/conf.d/ to align with artifactapi v2.7.1 directory loading.
Updated schema: virtuals/locals use dedicated top-level keys, type field
removed. Added helm remotes for all kustomize helmCharts repos and
OCI patterns to docker remotes. CONFIG_PATH now points to the directory.

Reviewed-on: #92

apps/base/artifactapi/resources/conf.d/virtual-helm.yaml

@@ -0,0 +1,16 @@
+virtuals:
+  helm:
+    package: "helm"
+    description: "Virtual repository merging all helm remotes — member order is priority order for duplicate chart+version"
+    members:
+      - ceph-csi
+      - cnpg
+      - elastic-helm
+      - external-dns
+      - hashicorp-helm
+      - intel-helm
+      - jetstack
+      - purelb
+      - rancher-stable
+      - stakater
+      - victoriametrics