Fix price fetch failing after market hours by adding 5-day daily fallback

period=1d interval=1m returns empty after NSE closes at 3:30 PM IST.
Fall back to period=5d interval=1d to get last available close price.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

indian_paper_trading_strategy/engine/data.py

@@ -1,4 +1,4 @@
-# engine/data.py
+# engine/data.py
 from datetime import datetime, timezone
 from pathlib import Path
 import os
@@ -6,11 +6,11 @@ import threading
 
 import pandas as pd
 import yfinance as yf
-
-ENGINE_ROOT = Path(__file__).resolve().parents[1]
-HISTORY_DIR = ENGINE_ROOT / "storage" / "history"
-ALLOW_PRICE_CACHE = os.getenv("ALLOW_PRICE_CACHE", "0").strip().lower() in {"1", "true", "yes"}
-
+
+ENGINE_ROOT = Path(__file__).resolve().parents[1]
+HISTORY_DIR = ENGINE_ROOT / "storage" / "history"
+ALLOW_PRICE_CACHE = os.getenv("ALLOW_PRICE_CACHE", "0").strip().lower() in {"1", "true", "yes"}
+
 _LAST_PRICE: dict[str, dict[str, object]] = {}
 _LAST_PRICE_LOCK = threading.Lock()
 
@@ -39,10 +39,10 @@ def _set_last_price(
 
 
 def get_price_snapshot(ticker: str) -> dict[str, object] | None:
-    with _LAST_PRICE_LOCK:
-        data = _LAST_PRICE.get(ticker)
-        if not data:
-            return None
+    with _LAST_PRICE_LOCK:
+        data = _LAST_PRICE.get(ticker)
+        if not data:
+            return None
         return dict(data)
 
 
@@ -78,14 +78,35 @@ def fetch_live_price(
 ):
     if allow_cache is None:
         allow_cache = ALLOW_PRICE_CACHE
+    # Try intraday (works during market hours)
     try:
         df = yf.download(
             ticker,
             period="1d",
             interval="1m",
-            auto_adjust=True,
-            progress=False,
-            timeout=5,
+            auto_adjust=True,
+            progress=False,
+            timeout=5,
+        )
+        if df is not None and not df.empty:
+            close_value = df["Close"].iloc[-1]
+            if hasattr(close_value, "iloc"):
+                close_value = close_value.iloc[-1]
+            price = float(close_value)
+            _set_last_price(ticker, price, "live", provider="yfinance")
+            return price
+    except Exception:
+        pass
+
+    # Fallback: last close from past 5 days (works after market hours)
+    try:
+        df = yf.download(
+            ticker,
+            period="5d",
+            interval="1d",
+            auto_adjust=True,
+            progress=False,
+            timeout=5,
         )
         if df is not None and not df.empty:
             close_value = df["Close"].iloc[-1]