debug: add db_state display + raw pred_json, expand YFINANCE_MAP

YFINANCE_MAP now includes GBPUSD, USDJPY, USDCHF, AUDUSD, NZDUSD, USDCAD, XAGUSD, NASDAQ, DAX, FTSE, WTI, US30Y, DXY.
Frontend diagnostic panel shows db_state rows after Recalculer and raw prediction_json prefix per event.

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

backend/routers/causal_lab.py

@@ -45,12 +45,25 @@ def _fetch_prices(event_date_str: str, instruments: list[str], lag_days: int = 0
     """
     YFINANCE_MAP = {
         "EURUSD": "EURUSD=X",
+        "GBPUSD": "GBPUSD=X",
+        "USDJPY": "USDJPY=X",
+        "USDCHF": "USDCHF=X",
+        "AUDUSD": "AUDUSD=X",
+        "NZDUSD": "NZDUSD=X",
+        "USDCAD": "USDCAD=X",
         "XAUUSD": "GC=F",
+        "XAGUSD": "SI=F",
         "SP500":  "^GSPC",
+        "NASDAQ": "^IXIC",
+        "DAX":    "^GDAXI",
+        "FTSE":   "^FTSE",
         "BRENT":  "BZ=F",
+        "WTI":    "CL=F",
         "US2Y":   "US2YT=RR",
         "US10Y":  "^TNX",
         "EU10Y":  "GE10YT=RR",
+        "US30Y":  "^TYX",
+        "DXY":    "DX-Y.NYB",
     }
 
     out: dict = {"mode": "none"}