Add risk leverage basis option: actual ask vs selection leverage.

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

backend/app/api/settings.py

@@ -50,6 +50,7 @@ KEYS = (
     "option_qty_eth",
     "show_manual_trade_buttons",
     "sizing_mode",
+    "risk_leverage_basis",
     "risk_loss_mode",
     "risk_loss_pct",
     "risk_loss_usdt",
@@ -86,6 +87,9 @@ class StrategySettingsBody(BaseModel):
     show_manual_trade_buttons: bool | None = None
     exchange: str | None = Field(default=None, pattern="^(okx|binance|bn)$")
     sizing_mode: str | None = Field(default=None, pattern="^(manual|risk_based)$")
+    risk_leverage_basis: str | None = Field(
+        default=None, pattern="^(actual|selection)$"
+    )
     risk_loss_mode: str | None = Field(default=None, pattern="^(percent|absolute)$")
     risk_loss_pct: float | None = Field(default=None, ge=0.01, le=100)
     risk_loss_usdt: float | None = Field(default=None, ge=0.1, le=1_000_000)
@@ -228,6 +232,23 @@ def _read_settings() -> dict:
             in ("manual", "risk_based")
             else "manual"
         ),
+        "risk_leverage_basis": (
+            rb
+            if (
+                rb := str(
+                    db.get_setting(
+                        "risk_leverage_basis",
+                        str(s.risk_leverage_basis),
+                    )
+                    or s.risk_leverage_basis
+                    or "selection"
+                )
+                .strip()
+                .lower()
+            )
+            in ("actual", "selection")
+            else "selection"
+        ),
         "risk_loss_mode": (
             lm
             if (