refactor: centralize numeric normalization

app/backend/features/market/insights.py

@@ -6,6 +6,7 @@ from datetime import datetime, time as dt_time, timedelta, timezone
 from statistics import median
 from typing import TYPE_CHECKING, Any, Callable
 
+from backend.data.numbers import non_nan_number as _number
 from backend.data.providers.ifind_client import IfindError, IfindHttpClient
 from backend.data.providers.tushare_client import TushareClient, TushareError
 
@@ -16,14 +17,6 @@ if TYPE_CHECKING:
 CHINA_TIMEZONE = timezone(timedelta(hours=8))
 
 
-def _number(value: Any, default: float = 0.0) -> float:
-    try:
-        number = float(value)
-        return number if number == number else default
-    except (TypeError, ValueError):
-        return default
-
-
 def _display_date(value: str) -> str:
     text = str(value or "").replace("-", "")
     if len(text) != 8:

app/backend/features/screener/engine.py

@@ -9,6 +9,7 @@ from datetime import datetime, timedelta
 from typing import Any
 
 from advanced_strategies import ADVANCED_CURATED_STRATEGIES
+from backend.data.numbers import finite_number as _number
 from database import ReviewDatabase
 from backend.features.sentiment.engine import build_sentiment_history, latest_contiguous_history
 from tushare_client import TushareClient, TushareError
@@ -2201,13 +2202,5 @@ def _regime_reason(regime: str) -> str:
     }.get(regime, "市场阶段待确认。")
 
 
-def _number(value: Any, default: float = 0.0) -> float:
-    try:
-        number = float(value)
-        return number if math.isfinite(number) else default
-    except (TypeError, ValueError):
-        return default
-
-
 def _display_date(value: str) -> str:
     return f"{value[:4]}-{value[4:6]}-{value[6:8]}" if len(value) == 8 else value

app/backend/features/sentiment/engine.py

@@ -4,6 +4,8 @@ from copy import deepcopy
 from statistics import mean, median
 from typing import Any
 
+from backend.data.numbers import non_nan_number as _number
+
 
 COMPONENT_WEIGHTS = {
     "breadth": 20,
@@ -16,14 +18,6 @@ COMPONENT_WEIGHTS = {
 SENTIMENT_ENGINE_VERSION = 2
 
 
-def _number(value: Any, default: float = 0.0) -> float:
-    try:
-        number = float(value)
-        return number if number == number else default
-    except (TypeError, ValueError):
-        return default
-
-
 def _clamp(value: float, lower: float = 0.0, upper: float = 100.0) -> float:
     return min(upper, max(lower, value))