refactor: centralize compact date formatting

app/ARCHITECTURE.md

@@ -28,6 +28,8 @@ background scheduler
 
 - `server.py` is the stable command/import facade. Runtime composition lives in
   `backend/application.py` and `backend/bootstrap/`.
+- `backend/bootstrap/` owns process configuration, dependency construction, startup, and
+  shared input/display-format contracts. It does not own feature behavior.
 - `backend/http/` owns common authentication, request IDs, responses, static delivery, and
   error normalization. Feature-specific transport handlers live beside their feature.
   Exact POST endpoints that only delegate to one of those handlers use the explicit maps in

app/backend/bootstrap/config.py

@@ -71,6 +71,10 @@ def normalize_date(value: str) -> str:
     return parsed.strftime("%Y%m%d")
 
 
+def display_compact_date(value: str) -> str:
+    return f"{value[:4]}-{value[4:6]}-{value[6:8]}" if len(value) == 8 else value
+
+
 def validate_stock_code(value: str) -> str:
     code = value.strip()
     if not re.fullmatch(r"\d{6}", code):

app/backend/data/providers/tushare_client.py

@@ -11,6 +11,7 @@ from datetime import datetime, time as dt_time, timedelta
 from threading import Lock
 from typing import Any, ClassVar
 
+from backend.bootstrap.config import display_compact_date as _display_date
 from backend.data.numbers import finite_number as _number
 from backend.features.sentiment.engine import apply_sentiment_to_dashboard
 
@@ -2007,10 +2008,6 @@ def _display_time(value: Any) -> str:
     return f"{raw[:2]}:{raw[2:4]}:{raw[4:6]}"
 
 
-def _display_date(value: str) -> str:
-    return f"{value[:4]}-{value[4:6]}-{value[6:8]}" if len(value) == 8 else value
-
-
 def _realtime_market_status(current_time: dt_time) -> str:
     if current_time < dt_time(9, 25):
         return "pre_open"

app/backend/features/screener/engine.py

@@ -8,6 +8,7 @@ from collections import defaultdict
 from datetime import datetime, timedelta
 from typing import Any
 
+from backend.bootstrap.config import display_compact_date as _display_date
 from backend.data.numbers import finite_number as _number
 from backend.data.providers.tushare_client import TushareClient, TushareError
 from backend.features.screener.strategies import ADVANCED_CURATED_STRATEGIES
@@ -2200,7 +2201,3 @@ def _regime_reason(regime: str) -> str:
         "divergence": "指数或核心仍强，但广度、封板质量开始分化。",
         "retreat": "情绪指标继续走弱，应提高筛选门槛并接受无候选结果。",
     }.get(regime, "市场阶段待确认。")
-
-
-def _display_date(value: str) -> str:
-    return f"{value[:4]}-{value[4:6]}-{value[6:8]}" if len(value) == 8 else value

app/config/architecture-inventory.json

@@ -230,6 +230,12 @@
       "path": "backend/data/numbers.py"
     }
   ],
+  "date_formatting": [
+    {
+      "function": "display_compact_date",
+      "path": "backend/bootstrap/config.py"
+    }
+  ],
   "llm_entrypoints": [
     {
       "function": "stream_with_mentor",
@@ -289,13 +295,13 @@
     },
     {
       "path": "backend/features/screener/engine.py",
-      "bytes": 108434,
+      "bytes": 108387,
-      "lines": 2206
+      "lines": 2203
     },
     {
       "path": "backend/data/providers/tushare_client.py",
-      "bytes": 94171,
+      "bytes": 94124,
-      "lines": 2168
+      "lines": 2165
     },
     {
       "path": "frontend/app.js",

app/tests/test_preservation_slice_market.py

@@ -146,6 +146,7 @@ class MarketSliceSourceEquivalenceTests(unittest.TestCase):
             self.assertEqual(sha256(ORIGINAL_ROOT / original), sha256(APP_ROOT / migrated))
         original_tushare = top_level_definitions(ORIGINAL_ROOT / "tushare_client.py")
         original_tushare.pop("_number")
+        original_tushare.pop("_display_date")
         self.assertEqual(
             original_tushare,
             top_level_definitions(APP_ROOT / "backend/data/providers/tushare_client.py"),
@@ -155,6 +156,13 @@ class MarketSliceSourceEquivalenceTests(unittest.TestCase):
             function_contract(APP_ROOT / "backend/data/numbers.py", "finite_number"),
         )
         self.assertIs(canonical_tushare._number, finite_number)
+        self.assertEqual(
+            function_contract(ORIGINAL_ROOT / "tushare_client.py", "_display_date"),
+            function_contract(
+                APP_ROOT / "backend/bootstrap/config.py", "display_compact_date"
+            ),
+        )
+        self.assertIs(canonical_tushare._display_date, bootstrap_config.display_compact_date)
         original_charts = top_level_definitions(ORIGINAL_ROOT / "chart_data_provider.py")
         original_charts.pop("_stock_market_code")
         self.assertEqual(

app/tests/test_preservation_slice_screener.py

@@ -9,6 +9,7 @@ import advanced_strategies
 import llm_strategy
 import screener
 import strategy_tracking
+from backend.bootstrap import config as bootstrap_config
 from backend.data.numbers import finite_number
 from backend.features.screener import compiler, engine, strategies, tracking
 from backend.features.screener import service as screener_service
@@ -151,12 +152,12 @@ class ScreenerSliceSourceEquivalenceTests(unittest.TestCase):
         self.assertEqual(
             module_contract(
                 ORIGINAL_ROOT / "screener.py",
-                excluded_definitions={"_number"},
+                excluded_definitions={"_display_date", "_number"},
                 exclude_imports=True,
             ),
             module_contract(
                 APP_ROOT / "backend" / "features" / "screener" / "engine.py",
-                excluded_definitions={"_number"},
+                excluded_definitions={"_display_date", "_number"},
                 exclude_imports=True,
             ),
         )
@@ -165,6 +166,13 @@ class ScreenerSliceSourceEquivalenceTests(unittest.TestCase):
             function_contract(APP_ROOT / "backend/data/numbers.py", "finite_number"),
         )
         self.assertIs(engine._number, finite_number)
+        self.assertEqual(
+            function_contract(ORIGINAL_ROOT / "screener.py", "_display_date"),
+            function_contract(
+                APP_ROOT / "backend/bootstrap/config.py", "display_compact_date"
+            ),
+        )
+        self.assertIs(engine._display_date, bootstrap_config.display_compact_date)
         self.assertEqual(
             class_methods(
                 ORIGINAL_ROOT / "backend" / "features" / "screener" / "tracking.py",

app/tools/build_architecture_inventory.py

@@ -159,6 +159,9 @@ def build() -> dict[str, Any]:
             {"function": "finite_number", "path": "backend/data/numbers.py"},
             {"function": "non_nan_number", "path": "backend/data/numbers.py"},
         ],
+        "date_formatting": [
+            {"function": "display_compact_date", "path": "backend/bootstrap/config.py"},
+        ],
         "llm_entrypoints": [
             {"function": "stream_with_mentor", "path": "backend/features/mentor/agent.py"},
             {"function": "interpret_heaven", "path": "backend/features/heaven/agent.py"},

docs/governance/code-reduction.md

@@ -23,6 +23,7 @@
 | CR-03 | 股票市场后缀转换 | Tushare业务与iFinD图表各保留一份完全相同的沪深京代码转换函数 | 图表复用`bootstrap/config.py::tushare_code`，只保留一份函数体 | 已完成 |
 | CR-04 | 数值归一化策略 | 四个业务模块分别保留两组完全相同的数值转换函数体 | 由`backend/data/numbers.py`集中拥有两种既有语义，消费者保留原局部别名 | 已完成 |
 | CR-05 | 根级兼容入口 | 正式后端仍有五处通过迁移兼容模块反向导入规范实现 | 正式代码改用规范路径；兼容入口只服务原公开导入契约 | 已完成 |
+| CR-06 | 紧凑日期显示 | Tushare与选股引擎各保留一份完全相同的`YYYYMMDD`显示转换 | 由`bootstrap/config.py`拥有唯一格式策略，消费者保留原局部别名 | 已完成 |
 
 ## CR-01验收口径
 
@@ -139,6 +140,28 @@
 本批基线为`xiaobai-reduction-04-numeric-normalization-20260801`；检查点为
 `xiaobai-reduction-05-compatibility-boundaries-20260801`。
 
+## CR-06验收口径
+
+- 只合并参数、函数体和异常行为完全相同的日期/文本转换；名称相似但空值、未来日期、错误文案或
+  输入格式不同的函数不得合并。
+- Tushare与选股引擎继续暴露局部`_display_date`名称，并分别指向唯一共享实现。
+- 原版两个`_display_date`函数必须分别与共享实现AST相等，所有原调用结果保持不变。
+- 市场洞察的日期显示函数会清理连字符并容忍空值，语义不同，必须继续独立保留。
+
+## CR-06结果
+
+- 删除Tushare与选股引擎内两个重复日期函数体，新增`display_compact_date`唯一策略；生产代码总
+  行数不增加，重复函数体由两份降为一份。
+- 架构清单登记日期格式唯一所有权；保持性测试改为未改范围AST相等、共享函数AST相等和运行时
+  对象身份三重契约，没有放宽原迁移门禁。
+- `normalize_date`、市场洞察日期显示、实时行情时间格式和会员日期边界因语义不同均原样保留。
+- 候选321项、纯`app/`导出258项、24个JavaScript文件、API/架构注册表、Git空白检查和SQLite
+  完整性检查通过；本批不涉及页面、CSS或浏览器行为。
+- 本批不修改日期输入规则、业务计算、选股结果、接口、数据库、数据源、LLM、权限或部署。
+
+本批基线为`xiaobai-reduction-05-compatibility-boundaries-20260801`；检查点为
+`xiaobai-reduction-06-date-formatting-20260801`。
+
 ## 人工验收记录
 
 - 2026-08-01：用户检查CR-02与CR-03运行结果，确认未发现明显异常。本记录仅表示本轮可见功能与