Go: implement ASR and TTS for Xinference (#15096)

### What problem does this PR solve?

implement ASR and TTS for Xinference

### Type of change

- [x] New Feature (non-breaking change which adds functionality)
- [x] Refactoring

test/unit_test/api/apps/sdk/test_dify_retrieval.py

@@ -97,7 +97,10 @@ def _load_dify_retrieval(monkeypatch, *, kb, accessible, request_body, chunks=No
     _stub(
         monkeypatch,
         "api.db.services.document_service",
-        DocumentService=SimpleNamespace(get_by_id=lambda _id: (True, SimpleNamespace(meta_fields={}))),
+        DocumentService=SimpleNamespace(
+            get_by_id=lambda _id: (True, SimpleNamespace(id=_id, meta_fields={})),
+            get_by_ids=lambda ids, cols=None: [SimpleNamespace(id=doc_id, meta_fields={}) for doc_id in ids],
+        ),
     )
     _stub(
         monkeypatch,