cloudapi: Move Services to an actual struct

This removes the need to make anonymous structs in the middle of the
Customizations request.

internal/cloudapi/v2/openapi.v2.yml

@@ -1139,23 +1139,7 @@ components:
           items:
             $ref: '#/components/schemas/Filesystem'
         services:
-          type: object
-          additionalProperties: false
-          properties:
-            enabled:
-              description: List of services to enable by default
-              type: array
-              minItems: 1
-              items:
-                type: string
-                example: "nftables"
-            disabled:
-              description: List of services to disable by default
-              type: array
-              minItems: 1
-              items:
-                type: string
-                example: "firewalld"
+            $ref: '#/components/schemas/Services'
         hostname:
           type: string
           description: Configures the hostname
@@ -1415,6 +1399,24 @@ components:
           description: Adds the key to the user's authorized_keys file
           example: |
             ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIASWitkOH4U874EdsBUnytb3bwvRggHlQlbYXl7n10v9
+    Services:
+      type: object
+      additionalProperties: false
+      properties:
+        enabled:
+          description: List of services to enable by default
+          type: array
+          minItems: 1
+          items:
+            type: string
+            example: "nftables"
+        disabled:
+          description: List of services to disable by default
+          type: array
+          minItems: 1
+          items:
+            type: string
+            example: "firewalld"
     Timezone:
       type: object
       description: Timezone configuration