fix(ts-sdk): unwrap v1.1 search response in client, fix TS2339 type errors

search() now unwraps { results: [...] } -> [...] internally (same
pattern getAll() already uses), so callers always get Array<Memory>.

Removes redundant unwrap logic from integration test helpers and
search.test.ts that caused TS2339 'Property results does not exist
on type never' — the false branch of Array.isArray() was unreachable
since search() is typed as returning Array<Memory>.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

mem0-ts/src/client/mem0.ts

@@ -298,7 +298,8 @@ export default class MemoryClient {
         body: JSON.stringify(payload),
       },
     );
-    return response;
+    // Unwrap v1.1 format: { results: [...] } → [...]
+    return Array.isArray(response) ? response : (response?.results ?? response);
   }
 
   async delete(memoryId: string): Promise<{ message: string }> {