Use hub exchange instances for calculator contract precision.

Load enabled instances from settings, fetch market info via /api/hub/market, and apply exchange-specific amount and price precision in trend and roll calculators.

Co-authored-by: Cursor <cursoragent@cursor.com>

crypto_monitor_gate_bot/app.py

@@ -9255,6 +9255,19 @@ def _hub_account_bundle():
     }
 
 
+def _hub_fetch_market(base=""):
+    from hub_market_info_lib import fetch_usdt_swap_market_info
+
+    return fetch_usdt_swap_market_info(
+        base_or_symbol=base,
+        normalize_symbol_input=normalize_symbol_input,
+        normalize_exchange_symbol=normalize_exchange_symbol,
+        ensure_markets_loaded=ensure_markets_loaded,
+        exchange=exchange,
+        exchange_id="gate_bot",
+    )
+
+
 def _hub_fetch_ohlcv(symbol, timeframe, since_ms=None, limit=500):
     from hub_ohlcv_lib import fetch_ohlcv_for_hub
 
@@ -9303,6 +9316,7 @@ try:
         views={"add_order": add_order, "add_key": add_key},
         ohlcv_fn=_hub_fetch_ohlcv,
         volume_rank_fn=_hub_fetch_volume_rank,
+        market_fn=_hub_fetch_market,
         reconcile_hub_flat_fn=reconcile_hub_external_close,
         risk_status_fn=hub_account_risk_status,
         user_close_fn=hub_user_initiated_close,