tests: update tests to use httpx.AsyncClient (#3984)

* Add async support and dependencies to pyproject.toml files

- Added `asgi-lifespan>=2.1.0` to dependencies.
- Configured `asyncio_mode` and `asyncio_default_fixture_loop_scope` for pytest.
- Updated `tool.uv` section with `asgi-lifespan` in dev-dependencies.

* Convert test fixtures to async and use AsyncClient for HTTP requests

* Handle 'ImportFrom' nodes in AST validation to support module attribute imports

* Convert test cases to use async HTTP client

- Updated test cases in `test_database.py`, `test_endpoints.py`, `test_user.py`, `test_variable.py`, `test_files.py`, `test_chat_endpoint.py`, `test_misc.py`, `test_messages_endpoints.py`, `test_api_key.py`, `test_webhook.py`, and `test_login.py` to use `httpx.AsyncClient` instead of `fastapi.TestClient`.
- Modified test functions to be asynchronous and use `await` for HTTP requests.
- Adjusted fixtures and helper functions to support asynchronous operations.
- Ensured consistency in endpoint paths and request methods across all test cases.

* Refactor string concatenation to f-string in test_chat_endpoint.py

* [autofix.ci] apply automated fixes

* Refactor import validation to use pattern matching for AST nodes

* Set `startup_timeout` and `shutdown_timeout` to `None` in `LifespanManager` for test files.

* Convert test functions to async in `test_messages_endpoints.py`

* Add `api_key_required` marker to assistant component tests

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

src/backend/tests/integration/test_misc.py

@@ -10,7 +10,7 @@ from langflow.load import run_flow_from_json
 
 
 @pytest.mark.api_key_required
-def test_run_flow_with_caching_success(client: TestClient, starter_project, created_api_key):
+async def test_run_flow_with_caching_success(client: TestClient, starter_project, created_api_key):
     flow_id = starter_project["id"]
     headers = {"x-api-key": created_api_key.api_key}
     payload = {
@@ -20,7 +20,7 @@ def test_run_flow_with_caching_success(client: TestClient, starter_project, crea
         "tweaks": {"parameter_name": "value"},
         "stream": False,
     }
-    response = client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
+    response = await client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
     assert response.status_code == status.HTTP_200_OK
     data = response.json()
     assert "outputs" in data
@@ -28,11 +28,11 @@ def test_run_flow_with_caching_success(client: TestClient, starter_project, crea
 
 
 @pytest.mark.api_key_required
-def test_run_flow_with_caching_invalid_flow_id(client: TestClient, created_api_key):
+async def test_run_flow_with_caching_invalid_flow_id(client: TestClient, created_api_key):
     invalid_flow_id = uuid4()
     headers = {"x-api-key": created_api_key.api_key}
     payload = {"input_value": "", "input_type": "text", "output_type": "text", "tweaks": {}, "stream": False}
-    response = client.post(f"/api/v1/run/{invalid_flow_id}", json=payload, headers=headers)
+    response = await client.post(f"/api/v1/run/{invalid_flow_id}", json=payload, headers=headers)
     assert response.status_code == status.HTTP_404_NOT_FOUND
     data = response.json()
     assert "detail" in data
@@ -40,16 +40,16 @@ def test_run_flow_with_caching_invalid_flow_id(client: TestClient, created_api_k
 
 
 @pytest.mark.api_key_required
-def test_run_flow_with_caching_invalid_input_format(client: TestClient, starter_project, created_api_key):
+async def test_run_flow_with_caching_invalid_input_format(client: TestClient, starter_project, created_api_key):
     flow_id = starter_project["id"]
     headers = {"x-api-key": created_api_key.api_key}
     payload = {"input_value": {"key": "value"}, "input_type": "text", "output_type": "text", "tweaks": {}}
-    response = client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
+    response = await client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
     assert response.status_code == status.HTTP_422_UNPROCESSABLE_ENTITY
 
 
 @pytest.mark.api_key_required
-def test_run_flow_with_invalid_tweaks(client, starter_project, created_api_key):
+async def test_run_flow_with_invalid_tweaks(client, starter_project, created_api_key):
     headers = {"x-api-key": created_api_key.api_key}
     flow_id = starter_project["id"]
     payload = {
@@ -58,12 +58,12 @@ def test_run_flow_with_invalid_tweaks(client, starter_project, created_api_key):
         "output_type": "text",
         "tweaks": {"invalid_tweak": "value"},
     }
-    response = client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
+    response = await client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
     assert response.status_code == status.HTTP_200_OK
 
 
 @pytest.mark.api_key_required
-def test_run_with_inputs_and_outputs(client, starter_project, created_api_key):
+async def test_run_with_inputs_and_outputs(client, starter_project, created_api_key):
     headers = {"x-api-key": created_api_key.api_key}
     flow_id = starter_project["id"]
     payload = {
@@ -73,7 +73,7 @@ def test_run_with_inputs_and_outputs(client, starter_project, created_api_key):
         "tweaks": {"parameter_name": "value"},
         "stream": False,
     }
-    response = client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
+    response = await client.post(f"/api/v1/run/{flow_id}", json=payload, headers=headers)
     assert response.status_code == status.HTTP_200_OK, response.text