feat: Phase 1+2 — project setup and core infrastructure

- requirements.txt, config.yaml, .env, Dockerfile, docker-compose.yml
- app/core: config (YAML+env override), logging (JSON structured),
  exceptions (typed hierarchy), json_utils (Markdown fence stripping)
- app/clients: LLMClient ABC + ZhipuAIClient (run_in_executor),
  StorageClient ABC + RustFSClient (boto3 head_object for size check)
- app/main.py: FastAPI app with health endpoint and router registration
- app/core/dependencies.py: lru_cache singleton factories
- tests/conftest.py: mock_llm, mock_storage, test_app, client fixtures
- pytest.ini: asyncio_mode=auto
- 11 unit tests passing

tests/test_storage_client.py

@@ -0,0 +1,62 @@
+import pytest
+from unittest.mock import MagicMock, patch
+from botocore.exceptions import ClientError
+
+from app.clients.storage.rustfs_client import RustFSClient
+from app.core.exceptions import StorageError
+
+
+@pytest.fixture
+def client():
+    with patch("app.clients.storage.rustfs_client.boto3") as mock_boto3:
+        c = RustFSClient(
+            endpoint="http://rustfs:9000",
+            access_key="key",
+            secret_key="secret",
+        )
+        c._s3 = MagicMock()
+        return c
+
+
+@pytest.mark.asyncio
+async def test_download_bytes_returns_bytes(client):
+    client._s3.get_object.return_value = {"Body": MagicMock(read=lambda: b"hello")}
+    result = await client.download_bytes("source-data", "text/test.txt")
+    assert result == b"hello"
+    client._s3.get_object.assert_called_once_with(Bucket="source-data", Key="text/test.txt")
+
+
+@pytest.mark.asyncio
+async def test_download_bytes_raises_storage_error(client):
+    client._s3.get_object.side_effect = ClientError(
+        {"Error": {"Code": "NoSuchKey", "Message": "Not Found"}}, "GetObject"
+    )
+    with pytest.raises(StorageError, match="存储下载失败"):
+        await client.download_bytes("source-data", "missing.txt")
+
+
+@pytest.mark.asyncio
+async def test_get_object_size_returns_content_length(client):
+    client._s3.head_object.return_value = {"ContentLength": 1024}
+    size = await client.get_object_size("source-data", "video/test.mp4")
+    assert size == 1024
+    client._s3.head_object.assert_called_once_with(Bucket="source-data", Key="video/test.mp4")
+
+
+@pytest.mark.asyncio
+async def test_get_object_size_raises_storage_error(client):
+    client._s3.head_object.side_effect = ClientError(
+        {"Error": {"Code": "NoSuchKey", "Message": "Not Found"}}, "HeadObject"
+    )
+    with pytest.raises(StorageError, match="获取文件大小失败"):
+        await client.get_object_size("source-data", "video/missing.mp4")
+
+
+@pytest.mark.asyncio
+async def test_upload_bytes_calls_put_object(client):
+    client._s3.put_object.return_value = {}
+    await client.upload_bytes("source-data", "frames/1/0.jpg", b"jpeg-data", "image/jpeg")
+    client._s3.put_object.assert_called_once()
+    call_kwargs = client._s3.put_object.call_args
+    assert call_kwargs.kwargs["Bucket"] == "source-data"
+    assert call_kwargs.kwargs["Key"] == "frames/1/0.jpg"