refactor: 统一代码格式，调整多行代码换行风格

对多个文件进行代码格式化调整，将长行参数拆分为多行书写，提升代码可读性，包括：
- 调整函数定义、调用的多行换行格式
- 优化列表、元组、字典的多行排版
- 新增README.md项目说明文档

tests/test_ingest_tasks.py

@@ -7,15 +7,28 @@ from datetime import datetime
 from typing import Any
 
 from app.config import Settings
-from app.core.ingest_tasks import DEDUP_KEY_PREFIX, REDIS_KEY_PREFIX, IngestTaskManager, IngestTaskStatus
+from app.core.ingest_tasks import (
+    DEDUP_KEY_PREFIX,
+    REDIS_KEY_PREFIX,
+    IngestTaskManager,
+    IngestTaskStatus,
+)
 from app.core.ingestion import IngestionError
-from app.models.document import DocumentInput, DocumentSummary, IngestionResult, SummaryLevel
+from app.models.document import (
+    DocumentInput,
+    DocumentSummary,
+    IngestionResult,
+    SummaryLevel,
+)
 
 
 def make_summary() -> DocumentSummary:
     """构造固定的三级总结"""
     return DocumentSummary(
-        l1_summary="一句话总结", l2_outline=None, l3_content_outline="内容大纲", level=SummaryLevel.L3
+        l1_summary="一句话总结",
+        l2_outline=None,
+        l3_content_outline="内容大纲",
+        level=SummaryLevel.L3,
     )
 
 
@@ -42,7 +55,9 @@ class FakeIngester:
         self.gate: asyncio.Event | None = None
         self.started = asyncio.Event()
 
-    async def ingest(self, doc: DocumentInput, progress_cb: Callable[[str], None] | None = None) -> IngestionResult:
+    async def ingest(
+        self, doc: DocumentInput, progress_cb: Callable[[str], None] | None = None
+    ) -> IngestionResult:
         self.calls.append(doc)
         self.started.set()
         if progress_cb is not None:
@@ -64,7 +79,9 @@ class FakeRedis:
         self.writes: list[tuple[str, dict[str, Any], int | None]] = []
         self.store: dict[str, dict[str, Any]] = {}
 
-    async def set_json(self, key: str, value: dict[str, Any], ttl: int | None = None) -> bool:
+    async def set_json(
+        self, key: str, value: dict[str, Any], ttl: int | None = None
+    ) -> bool:
         self.writes.append((key, value, ttl))
         if self.fail_writes:
             raise RuntimeError("redis down")
@@ -105,8 +122,12 @@ async def test_submit_returns_immediately_and_completes() -> None:
 
 async def test_ingestion_error_marks_failed_with_stage_and_partial_summary() -> None:
     """IngestionError：任务 failed，error.stage 透传，partial_summary 保留"""
-    summary = DocumentSummary(l1_summary="L1", l2_outline=None, l3_content_outline="L3", level=SummaryLevel.L3)
-    ingester = FakeIngester(error=IngestionError("classify", "分类判定失败: boom", summary=summary))
+    summary = DocumentSummary(
+        l1_summary="L1", l2_outline=None, l3_content_outline="L3", level=SummaryLevel.L3
+    )
+    ingester = FakeIngester(
+        error=IngestionError("classify", "分类判定失败: boom", summary=summary)
+    )
     manager = IngestTaskManager(ingester, FakeRedis(), Settings())
 
     task_id = await manager.submit(DocumentInput(text="正文"))
@@ -179,10 +200,14 @@ async def test_redis_mirror_ttl_done_and_failed() -> None:
     assert done_writes[-1][0]["status"] == IngestTaskStatus.DONE
 
     redis2 = FakeRedis()
-    failing_manager = IngestTaskManager(FakeIngester(error=RuntimeError("boom")), redis2, settings)
+    failing_manager = IngestTaskManager(
+        FakeIngester(error=RuntimeError("boom")), redis2, settings
+    )
     failed_id = await failing_manager.submit(DocumentInput(text="y"))
     await failing_manager.wait_done(failed_id, timeout=5)
-    failed_writes = [(v, ttl) for key, v, ttl in redis2.writes if key.endswith(failed_id)]
+    failed_writes = [
+        (v, ttl) for key, v, ttl in redis2.writes if key.endswith(failed_id)
+    ]
     assert failed_writes
     assert failed_writes[-1][0]["status"] == IngestTaskStatus.FAILED
     assert failed_writes[-1][1] == 604800
@@ -275,6 +300,7 @@ async def test_dedup_skipped_when_redis_unavailable() -> None:
 
 async def test_dedup_lookup_failure_falls_back_to_normal_pipeline() -> None:
     """Redis get_json 抛错：去重查询降级为未命中，走原流水线"""
+
     class _ExplodingRedis(FakeRedis):
         async def get_json(self, key: str) -> dict[str, Any] | None:
             raise RuntimeError("redis down")