feat(builtin_templates): add description field for text snippets

apps/server/src/services/hidden_subtree_templates.ts

@@ -18,6 +18,11 @@ export default function buildHiddenSubtreeTemplates() {
                     {
                         name: "textSnippet",
                         type: "label"
+                    },
+                    {
+                        name: "label:textSnippetDescription",
+                        type: "label",
+                        value: "promoted,alias=Description,single,text"
                     }
                 ]
             }

packages/commons/src/lib/hidden_subtree.ts

@@ -12,7 +12,7 @@ enum Command {
 }
 
 export interface HiddenSubtreeAttribute {
-    type: AttributeType;
+    type: "label" | "relation";
     name: string;
     isInheritable?: boolean;
     value?: string;