将 native/api/ 改名为 native/wndb/，避免与 Web API 层命名冲突

QUICK_START_GUIDE.md

@@ -84,7 +84,7 @@ async def get_reports(user: UserInDB = Depends(require_viewer)):
 ## 4️⃣ Call Native (Binary) Code
 
 ```python
-from app.native.api import get_all_junctions, add_junction, set_junction
+from app.native.wndb import get_all_junctions, add_junction, set_junction
 
 # Read network elements
 junctions = get_all_junctions()
@@ -96,7 +96,7 @@ add_junction({"id": "J1", "x": 0.0, "y": 0.0, "demand": 100.0})
 set_junction("J1", {"demand": 150.0})
 
 # Get constants
-from app.native.api import PIPE_STATUS_OPEN, OPTION_UNITS_LPS
+from app.native.wndb import PIPE_STATUS_OPEN, OPTION_UNITS_LPS
 ```
 
 ---
@@ -174,7 +174,7 @@ pytest tests/unit/test_my_feature.py::test_my_function -v
 | `app/domain/` | Models/Schemas | Data structures |
 | `app/infra/db/` | DB access | Queries, repositories |
 | `app/services/` | Business logic | Complex operations |
-| `app/native/api/` | Binary functions | Network simulation |
+| `app/native/wndb/` | Binary functions | Network simulation |
 | `app/core/` | Core utilities | Config, security, encryption |
 | `tests/` | Tests | Unit & integration tests |
 
@@ -203,7 +203,7 @@ from app.core.encryption import get_encryptor
 from app.core.config import settings
 
 # Native API
-from app.native.api import get_all_junctions, add_junction, open_project
+from app.native.wndb import get_all_junctions, add_junction, open_project
 ```
 
 ---