feat: 扩展 Rust gateway 全功能模块，新增 billing/crypto/wallet crate 及完整数据层

- 新增 aether-billing、aether-crypto、aether-wallet 独立 crate
- aether-data 扩展 repository 层：announcements、auth_modules、billing、
  candidate_selection、gemini_file_mappings、global_models、management_tokens、
  oauth_providers、proxy_nodes、quota、users、wallet 等模块
- aether-gateway 新增 api/auth/billing/control/middleware/scheduler/usage/
  video_tasks/hooks/maintenance/model_fetch/provider_transport 等功能模块
- 重构 executor decision 和 gateway state 为模块目录结构
- 新增 gateway router、frontdoor 路由层及对应测试
- Python 侧 API 路由重构，新增 compat/support 模块
- 前端 Logo 组件更新及 Provider 管理页面调整

tests/api/internal_gateway/test_gateway_trace.py

@@ -273,3 +273,81 @@ def test_record_gateway_direct_candidate_graph_uses_selected_pool_key_index() ->
         assert rows[0].status == "unused"
         assert rows[1].status == "pending"
         assert getattr(candidate, "request_candidate_id") == rows[1].id
+
+
+def test_record_gateway_direct_candidate_graph_is_idempotent_for_same_request_id() -> None:
+    engine = create_engine("sqlite:///:memory:")
+    Base.metadata.create_all(engine, tables=[RequestCandidate.__table__])
+    SessionLocal = sessionmaker(bind=engine)
+
+    with SessionLocal() as db:
+        resolver = CandidateResolver(db=db, cache_scheduler=SimpleNamespace())
+        user_api_key = SimpleNamespace(
+            id="api-key-direct-idempotent-123",
+            name="client-key",
+            user_id="user-direct-idempotent-123",
+            user=SimpleNamespace(id="user-direct-idempotent-123", username="direct-user"),
+        )
+        request_id = "req-direct-candidate-idempotent-123"
+        first_candidates = [
+            ProviderCandidate(
+                provider=SimpleNamespace(id="provider-selected-123", name="openai", max_retries=1),
+                endpoint=SimpleNamespace(id="endpoint-selected-123"),
+                key=SimpleNamespace(id="key-selected-123"),
+                provider_api_format="openai:cli",
+            ),
+            ProviderCandidate(
+                provider=SimpleNamespace(id="provider-unused-123", name="openai", max_retries=1),
+                endpoint=SimpleNamespace(id="endpoint-unused-123"),
+                key=SimpleNamespace(id="key-unused-123"),
+                provider_api_format="openai:cli",
+            ),
+        ]
+
+        _record_gateway_direct_candidate_graph(
+            db=db,
+            candidate_resolver=resolver,
+            candidates=first_candidates,
+            request_id=request_id,
+            user_api_key=user_api_key,
+            required_capabilities=None,
+            selected_candidate_index=0,
+        )
+        first_selected_record_id = getattr(first_candidates[0], "request_candidate_id")
+
+        second_candidates = [
+            ProviderCandidate(
+                provider=SimpleNamespace(id="provider-selected-123", name="openai", max_retries=1),
+                endpoint=SimpleNamespace(id="endpoint-selected-123"),
+                key=SimpleNamespace(id="key-selected-123"),
+                provider_api_format="openai:cli",
+            ),
+            ProviderCandidate(
+                provider=SimpleNamespace(id="provider-unused-123", name="openai", max_retries=1),
+                endpoint=SimpleNamespace(id="endpoint-unused-123"),
+                key=SimpleNamespace(id="key-unused-123"),
+                provider_api_format="openai:cli",
+            ),
+        ]
+
+        _record_gateway_direct_candidate_graph(
+            db=db,
+            candidate_resolver=resolver,
+            candidates=second_candidates,
+            request_id=request_id,
+            user_api_key=user_api_key,
+            required_capabilities=None,
+            selected_candidate_index=0,
+        )
+
+        rows = (
+            db.query(RequestCandidate)
+            .filter(RequestCandidate.request_id == request_id)
+            .order_by(RequestCandidate.candidate_index, RequestCandidate.retry_index)
+            .all()
+        )
+
+        assert len(rows) == 2
+        assert rows[0].status == "pending"
+        assert rows[1].status == "unused"
+        assert getattr(second_candidates[0], "request_candidate_id") == first_selected_record_id