fix: spot-perp basis floating-point EPS, NORMAL regime fallback, realistic fee defaults

strategies/spot_perp_basis.py

@@ -30,6 +30,8 @@ import numpy as np
 
 logger = logging.getLogger(__name__)
 
+EPS = 1e-10
+
 
 class SpotPerpBasisArb:
     """Delta-neutral spot-perpetual basis arbitrage.
@@ -47,13 +49,13 @@ class SpotPerpBasisArb:
     
     def __init__(
         self,
-        entry_threshold_bps: float = 3.0,
+        entry_threshold_bps: float = 5.0,
         exit_threshold_bps: float = 1.0,
         max_hold_hours: float = 48.0,
         size_usd: float = 1000.0,
-        spot_fee_rate: float = 0.0010,
-        perp_fee_rate: float = 0.0007,
-        min_expected_profit_bps: float = 1.5,
+        spot_fee_rate: float = 0.0004,
+        perp_fee_rate: float = 0.00015,
+        min_expected_profit_bps: float = 1.0,
     ):
         self.entry_threshold = entry_threshold_bps / 10000  # bps → decimal
         self.exit_threshold = exit_threshold_bps / 10000
@@ -112,7 +114,7 @@ class SpotPerpBasisArb:
         funding_apr = abs(funding_rate) * 365 * 3  # 8h → annual
         funding_profit = funding_apr * (self.max_hold_hours / (365 * 24))
 
-        if not in_position and abs(basis) > self.entry_threshold and expected_profit > self.min_expected_profit:
+        if not in_position and abs(basis) > self.entry_threshold and expected_profit >= self.min_expected_profit - EPS:
             if basis > 0:
                 return {
                     "action": "SELL_PERP_BUY_SPOT",
@@ -237,7 +239,7 @@ def multi_asset_basis_scan(
             continue
 
         basis = (perp - spot) / spot
-        if abs(basis) > entry_threshold_bps / 10000:
+        if abs(basis) >= entry_threshold_bps / 10000 - EPS:
             opportunities.append({
                 "coin": coin,
                 "spot": spot,