refactor(search): simplify order by + wire reverse

frontend/src/lib/api/endpoints/search.test.ts

@@ -16,12 +16,12 @@ it('builds search requests including filters', async () => {
 		fileTypes: ['mp3', 'wav'],
 		minSize: 1,
 		maxSize: 9,
-		sortBy: 'date'
+		sortBy: 'updated_at'
 	}).catch(() => {});
 	expect(j).toHaveBeenCalledWith(expect.stringContaining('type=mp3%2Cwav'), expect.anything());
 	// Sort dimension is sent on the wire as `order_by`, matching the
 	// backend's `SearchResourcesQuery` (post-normalization).
-	expect(j).toHaveBeenCalledWith(expect.stringContaining('order_by=date'), expect.anything());
+	expect(j).toHaveBeenCalledWith(expect.stringContaining('order_by=updated_at'), expect.anything());
 	await searchSuggest('q').catch(() => {});
 	await clearSearchCache().catch(() => {});
 	expect(f.mock.calls.length + j.mock.calls.length).toBeGreaterThan(1);

frontend/src/lib/api/types.ts

@@ -248,14 +248,14 @@ export interface AuthResponse {
 	expires_in: number;
 }
 
-export type SortBy =
-	| 'relevance'
-	| 'name'
-	| 'name_desc'
-	| 'date'
-	| 'date_desc'
-	| 'size'
-	| 'size_desc';
+/**
+ * Sort dimension for `GET /api/search`. Wire-matches the backend's
+ * `SearchResourcesQuery.order_by` — 5 canonical values, direction is
+ * a separate `reverse` boolean (the `_desc` suffix pattern was
+ * retired 2026-07-26; `date` was renamed to the more explicit
+ * `updated_at` alongside the new `created_at`).
+ */
+export type SortBy = 'relevance' | 'name' | 'size' | 'updated_at' | 'created_at';
 
 /**
  * Per-item search metadata inline on every hit in the normalized