feat(proxmox): better node-level routes auto-discovery with pointer VMID

- Add BaseURL field to Client for node-level route configuration
- Change VMID from int to *int to support three states:
  - nil: auto-discover node or VM from hostname/IP/alias
  - 0: node-level route (direct to Proxmox node API)
  - >0: LXC/QEMU resource route with container control
- Change Service string to Services []string for multi-service support
- Implement proper node-level route handling: HTTPS scheme,
  hostname from node BaseURL, default port 8006
- Move initial UpdateResources call to Init before starting loop
- Move proxmox auto-discovery earlier in route validation

BREAKING: NodeConfig.VMID is now a pointer type; NodeConfig.Service
renamed to Services (backward compatible via alias)

internal/proxmox/config.go

@@ -96,6 +96,15 @@ func (c *Config) Init(ctx context.Context) gperr.Error {
 		return gperr.New("failed to fetch proxmox cluster info").With(err)
 	}
 
+	{
+		reqCtx, reqCtxCancel := context.WithTimeout(ctx, ResourcePollInterval)
+		err := c.client.UpdateResources(reqCtx)
+		reqCtxCancel()
+		if err != nil {
+			log.Warn().Err(err).Str("cluster", c.client.Cluster.Name).Msg("[proxmox] failed to update resources")
+		}
+	}
+
 	go c.updateResourcesLoop(ctx)
 	return nil
 }
@@ -106,15 +115,6 @@ func (c *Config) updateResourcesLoop(ctx context.Context) {
 
 	log.Trace().Str("cluster", c.client.Cluster.Name).Msg("[proxmox] starting resources update loop")
 
-	{
-		reqCtx, reqCtxCancel := context.WithTimeout(ctx, ResourcePollInterval)
-		err := c.client.UpdateResources(reqCtx)
-		reqCtxCancel()
-		if err != nil {
-			log.Warn().Err(err).Str("cluster", c.client.Cluster.Name).Msg("[proxmox] failed to update resources")
-		}
-	}
-
 	for {
 		select {
 		case <-ctx.Done():