frontend-plugin-api: refactor extension "at" option to "attachTo"

Co-authored-by: Camila Belo <camilaibs@gmail.com>
Co-authored-by: Fredrik Adelöw <freben@gmail.com>
Co-authored-by: Vincenzo Scamporlino <vincenzos@spotify.com>
Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

plugins/search-react/src/alpha.test.tsx

@@ -58,7 +58,7 @@ describe('createSearchResultListItemExtension', () => {
     const TechDocsSearchResultItemExtension =
       createSearchResultListItemExtension({
         id: 'techdocs',
-        at: 'plugin.search.page/items',
+        attachTo: { id: 'plugin.search.page', input: 'items' },
         configSchema: createSchemaFromZod(z =>
           z.object({
             noTrack: z.boolean().default(true),
@@ -79,7 +79,7 @@ describe('createSearchResultListItemExtension', () => {
     const ExploreSearchResultItemExtension =
       createSearchResultListItemExtension({
         id: 'explore',
-        at: 'plugin.search.page/items',
+        attachTo: { id: 'plugin.search.page', input: 'items' },
         predicate: result => result.type === 'explore',
         component: async () => ExploreSearchResultItemComponent,
       });

plugins/search-react/src/alpha.tsx

@@ -65,7 +65,7 @@ export type SearchResultItemExtensionOptions<
   /**
    * The extension attachment point (e.g., search modal or page).
    */
-  at?: string;
+  attachTo?: { id: string; input: string };
   /**
    * Optional extension config schema.
    */
@@ -97,7 +97,7 @@ export function createSearchResultListItemExtension<
         ) as PortableSchema<TConfig>);
   return createExtension({
     id: `plugin.search.result.item.${options.id}`,
-    at: options.at ?? 'plugin.search.page/items',
+    attachTo: options.attachTo ?? { id: 'plugin.search.page', input: 'items' },
     configSchema,
     output: {
       item: searchResultItemExtensionData,