Fix short id form field

src/photo/form.ts

@@ -19,11 +19,21 @@ type FormMeta = {
   hideTemporarily?: boolean
 };
 
-const FORM_METADATA: Record<keyof PhotoFormData, FormMeta> = {
+const FORM_METADATA: Record<
+  // Display short ids as a convenience
+  // even though they're not part of form data
+  keyof PhotoFormData & { idShort?: string },
+  FormMeta
+> = {
   title: { label: 'title' },
   tags: { label: 'tags', note: 'comma-separated values' },
   id: { label: 'id', readOnly: true, hideIfEmpty: true },
-  idShort: { label: 'short id', readOnly: true, hideIfEmpty: true },
+  idShort: {
+    label: 'short id',
+    readOnly: true,
+    hideIfEmpty: true,
+    note: 'Auto-generated by id',
+  },
   url: { label: 'url', readOnly: true },
   extension: { label: 'extension', readOnly: true },
   aspectRatio: { label: 'aspect ratio', readOnly: true },