feat(docker): allow vm and proxmox as parent for docker_container

Extend docker_container parent rule to accept vm and proxmox nodes
in addition to docker_host and lxc, covering nested virtualization
topologies (Docker on a VM, Docker directly on Proxmox host).

ha-relevant: yes

frontend/src/utils/__tests__/virtualEdgeParent.test.ts

@@ -42,7 +42,23 @@ describe('resolveVirtualEdgeParent', () => {
     expect(res).toEqual({ childId: 'dc1', parentId: 'lxc1' })
   })
 
-  it('returns null when docker_container links to non-host/lxc target', () => {
+  it('nests docker_container under vm', () => {
+    const res = resolveVirtualEdgeParent(
+      { id: 'dc1', type: 'docker_container' },
+      { id: 'vm1', type: 'vm' },
+    )
+    expect(res).toEqual({ childId: 'dc1', parentId: 'vm1' })
+  })
+
+  it('nests docker_container under proxmox (reverse direction)', () => {
+    const res = resolveVirtualEdgeParent(
+      { id: 'px1', type: 'proxmox' },
+      { id: 'dc1', type: 'docker_container' },
+    )
+    expect(res).toEqual({ childId: 'dc1', parentId: 'px1' })
+  })
+
+  it('returns null when docker_container links to unsupported parent type', () => {
     const res = resolveVirtualEdgeParent(
       { id: 'dc1', type: 'docker_container' },
       { id: 'srv1', type: 'server' },

frontend/src/utils/virtualEdgeParent.ts

@@ -3,6 +3,7 @@ import type { NodeData } from '@/types'
 export type NodeType = NodeData['type']
 
 const CONTAINER_MODE_TYPES = new Set<NodeType>(['proxmox', 'vm', 'lxc', 'docker_host'])
+const DOCKER_CONTAINER_PARENT_TYPES = new Set<NodeType>(['docker_host', 'lxc', 'vm', 'proxmox'])
 
 export interface VirtualEdgeEndpoint {
   id: string
@@ -27,10 +28,10 @@ export function resolveVirtualEdgeParent(
   if (CONTAINER_MODE_TYPES.has(srcType) && (tgtType === 'lxc' || tgtType === 'vm')) {
     return { childId: tgtId, parentId: srcId }
   }
-  if (srcType === 'docker_container' && (tgtType === 'docker_host' || tgtType === 'lxc')) {
+  if (srcType === 'docker_container' && DOCKER_CONTAINER_PARENT_TYPES.has(tgtType)) {
     return { childId: srcId, parentId: tgtId }
   }
-  if (tgtType === 'docker_container' && (srcType === 'docker_host' || srcType === 'lxc')) {
+  if (tgtType === 'docker_container' && DOCKER_CONTAINER_PARENT_TYPES.has(srcType)) {
     return { childId: tgtId, parentId: srcId }
   }
   return null