refactor(storage): route project DSNs and remove legacy backends

tests/api/test_model_import_endpoints.py

@@ -10,6 +10,8 @@ from app.auth.metadata_dependencies import (
     get_current_metadata_admin,
     get_metadata_repository,
 )
+from app.infra.db.metadb.repositories.metadata_repository import ProjectDbRouting
+from app.infra.db.project_routing import get_project_pgconn_string
 from tests.conftest import build_test_app
 
 
@@ -98,3 +100,47 @@ def test_model_import_rejects_non_inp_file(monkeypatch):
     assert response.status_code == 400
     assert response.json()["detail"] == "Only .inp model files are accepted"
     model_import.log_audit_event.assert_not_awaited()
+
+
+def test_model_update_uses_project_business_routing(monkeypatch):
+    project_id = uuid4()
+    project = SimpleNamespace(id=project_id, code="demo", status="active")
+    repo = SimpleNamespace(
+        session=object(),
+        get_project_by_id=AsyncMock(return_value=project),
+        get_project_db_routing=AsyncMock(
+            return_value=ProjectDbRouting(
+                project_id=project_id,
+                db_role="biz_data",
+                db_type="postgresql",
+                dsn="postgresql://user:password@biz.example/routed_business",
+                pool_min_size=1,
+                pool_max_size=5,
+            )
+        ),
+    )
+    captured: dict[str, str] = {}
+
+    async def fake_apply_model_update(content: bytes, project_code: str) -> None:
+        assert content == VALID_INP
+        captured["project_code"] = project_code
+        captured["dsn"] = get_project_pgconn_string(project_code)
+
+    monkeypatch.setattr(model_import, "_apply_model_update", fake_apply_model_update)
+    monkeypatch.setattr(model_import, "log_audit_event", AsyncMock())
+    client = _client(
+        admin=SimpleNamespace(id=uuid4(), role="admin", is_superuser=False),
+        repo=repo,
+    )
+
+    response = client.patch(
+        f"/api/v1/admin/projects/{project_id}/model-imports",
+        files={"file": ("desktop-model.inp", VALID_INP)},
+    )
+
+    assert response.status_code == 200
+    assert captured == {
+        "project_code": "demo",
+        "dsn": "postgresql://user:password@biz.example/routed_business",
+    }
+    repo.get_project_db_routing.assert_awaited_once_with(project_id, "biz_data")