fix(admin): 优先级脏检查、base_url 校验、usage detail 延迟加载及导入数据验证

- 前端优先级管理: 保存时对比原始快照，仅提交实际变更的 provider/key 优先级，
  并限制并发请求数(SAVE_CONCURRENCY=6)，避免无效 API 调用
- handler_adapter_base: _normalize_test_base_url 改为 _validate_test_base_url，
  移除对 dict 类型 base_url 的兼容，严格要求字符串输入
- provider_query: 新增 _require_test_endpoint_base_url，在测试链路提前校验
  endpoint.base_url 类型和非空
- system.py: 导入 endpoint 时通过 ProviderEndpointCreate 模型校验数据，
  拒绝非法 base_url 类型(如 dict)
- usage detail: 使用 defer() 延迟加载 body 列，通过 SQL CASE 表达式在
  数据库端计算 has_*_body 标记，减少不必要的大字段传输
- provider routes: 新建 provider 时 priority=0 边界处理，clamp 并 shift

tests/api/test_admin_usage_routes.py

@@ -7,7 +7,7 @@ from typing import Any
 
 import pytest
 
-from src.api.admin.usage.routes import AdminUsageRecordsAdapter
+from src.api.admin.usage.routes import AdminUsageDetailAdapter, AdminUsageRecordsAdapter
 
 
 class _FakeQuery:
@@ -16,9 +16,11 @@ class _FakeQuery:
         *,
         scalar_result: int | None = None,
         all_result: list[Any] | None = None,
+        first_result: Any = None,
     ) -> None:
         self.scalar_result = scalar_result
         self.all_result = all_result or []
+        self.first_result = first_result
         self.options_args: tuple[Any, ...] = ()
 
     def outerjoin(self, *args: Any, **kwargs: Any) -> _FakeQuery:
@@ -49,6 +51,9 @@ class _FakeQuery:
     def all(self) -> list[Any]:
         return self.all_result
 
+    def first(self) -> Any:
+        return self.first_result
+
 
 class _FakeDb:
     def __init__(self, queries: list[_FakeQuery]) -> None:
@@ -141,3 +146,130 @@ async def test_admin_usage_records_returns_model_version_without_request_metadat
     usage_load_only = data_query.options_args[0]
     usage_paths = {str(option.path) for option in usage_load_only.context}
     assert "ORM Path[Mapper[Usage(usage)] -> Usage.request_metadata]" not in usage_paths
+
+
+@pytest.mark.asyncio
+async def test_admin_usage_detail_defers_large_body_columns_when_bodies_excluded(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    async def _fake_get_tiered_pricing_info(
+        self: AdminUsageDetailAdapter,
+        db: Any,
+        usage_record: Any,
+    ) -> None:
+        return None
+
+    monkeypatch.setattr(
+        AdminUsageDetailAdapter,
+        "_get_tiered_pricing_info",
+        _fake_get_tiered_pricing_info,
+    )
+    monkeypatch.setattr(
+        AdminUsageDetailAdapter,
+        "_extract_video_billing_info",
+        lambda self, usage_record: None,
+    )
+
+    class _UsageRecord:
+        id = "usage-1"
+        request_id = "req-1"
+        user_id = "user-1"
+        api_key_id = "key-1"
+        provider_name = "openai"
+        api_format = "openai:cli"
+        model = "gpt-5.4"
+        target_model = None
+        input_tokens = 10
+        output_tokens = 20
+        total_tokens = 30
+        cache_creation_input_tokens = 0
+        cache_read_input_tokens = 0
+        cache_creation_input_tokens_5m = 0
+        cache_creation_input_tokens_1h = 0
+        input_cost_usd = Decimal("0.001")
+        output_cost_usd = Decimal("0.002")
+        total_cost_usd = Decimal("0.003")
+        cache_creation_cost_usd = Decimal("0")
+        cache_read_cost_usd = Decimal("0")
+        request_cost_usd = Decimal("0")
+        input_price_per_1m = Decimal("0.1")
+        output_price_per_1m = Decimal("0.2")
+        cache_creation_price_per_1m = None
+        cache_read_price_per_1m = None
+        price_per_request = None
+        request_type = "chat"
+        is_stream = True
+        status_code = 200
+        error_message = None
+        status = "completed"
+        response_time_ms = 1200
+        first_byte_time_ms = 200
+        created_at = datetime(2026, 3, 12, 7, 0, tzinfo=timezone.utc)
+        request_headers = {"x-test": "1"}
+        provider_request_headers = {"authorization": "***"}
+        response_headers = {"content-type": "text/event-stream"}
+        client_response_headers = {"content-type": "text/event-stream"}
+        request_metadata = {"trace_id": "trace-1"}
+
+        def get_request_body(self) -> Any:
+            raise AssertionError("request body should not be loaded")
+
+        def get_provider_request_body(self) -> Any:
+            raise AssertionError("provider request body should not be loaded")
+
+        def get_response_body(self) -> Any:
+            raise AssertionError("response body should not be loaded")
+
+        def get_client_response_body(self) -> Any:
+            raise AssertionError("client response body should not be loaded")
+
+    class _ApiKeyRecord:
+        id = "key-1"
+        name = "Primary"
+
+        def get_display_key(self) -> str:
+            return "sk-test"
+
+    usage_query = _FakeQuery(
+        first_result=(_UsageRecord(), True, True, True, True),
+    )
+    user_query = _FakeQuery(
+        first_result=SimpleNamespace(id="user-1", username="tester", email="u@example.com"),
+    )
+    api_key_query = _FakeQuery(first_result=_ApiKeyRecord())
+    db = _FakeDb([usage_query, user_query, api_key_query])
+    context = SimpleNamespace(
+        db=db,
+        user=SimpleNamespace(id="admin-1"),
+        add_audit_metadata=lambda **_: None,
+    )
+
+    adapter = AdminUsageDetailAdapter(usage_id="usage-1", include_bodies=False)
+    result = await adapter.handle(context)  # type: ignore[arg-type]
+
+    assert result["request_body"] is None
+    assert result["provider_request_body"] is None
+    assert result["response_body"] is None
+    assert result["client_response_body"] is None
+    assert result["has_request_body"] is True
+    assert result["has_provider_request_body"] is True
+    assert result["has_response_body"] is True
+    assert result["has_client_response_body"] is True
+
+    deferred_paths = {
+        str(context.path)
+        for option in usage_query.options_args
+        for context in getattr(option, "context", ())
+    }
+    assert "ORM Path[Mapper[Usage(usage)] -> Usage.request_body]" in deferred_paths
+    assert "ORM Path[Mapper[Usage(usage)] -> Usage.provider_request_body]" in deferred_paths
+    assert "ORM Path[Mapper[Usage(usage)] -> Usage.response_body]" in deferred_paths
+    assert "ORM Path[Mapper[Usage(usage)] -> Usage.client_response_body]" in deferred_paths
+    assert "ORM Path[Mapper[Usage(usage)] -> Usage.request_body_compressed]" in deferred_paths
+    assert (
+        "ORM Path[Mapper[Usage(usage)] -> Usage.provider_request_body_compressed]" in deferred_paths
+    )
+    assert "ORM Path[Mapper[Usage(usage)] -> Usage.response_body_compressed]" in deferred_paths
+    assert (
+        "ORM Path[Mapper[Usage(usage)] -> Usage.client_response_body_compressed]" in deferred_paths
+    )