fix: show risk amount only in full-margin mode across four exchanges

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

position_sizing_lib.py

@@ -53,6 +53,42 @@ def round_funds(value: float, decimals: int = 2) -> float:
     return round(float(value), int(decimals))
 
 
+def risk_percent_for_storage(mode: str, risk_percent: float) -> Optional[float]:
+    """全仓杠杆：库内不写风险百分比（仅 risk_amount U）。"""
+    if is_full_margin_mode(mode):
+        return None
+    return risk_percent
+
+
+def format_risk_display_text(
+    mode: str,
+    risk_percent: Optional[float],
+    risk_amount: Optional[float],
+    *,
+    decimals: int = 2,
+) -> str:
+    """持仓/通知「风险」文案：全仓仅 U；以损定仓为 %≈U。"""
+    amt: Optional[float] = None
+    if risk_amount is not None and risk_amount != "":
+        try:
+            amt = float(risk_amount)
+        except (TypeError, ValueError):
+            amt = None
+    if is_full_margin_mode(mode):
+        if amt is None:
+            return "—"
+        return f"{round_funds(amt, decimals)}U"
+    pct: Optional[float] = None
+    if risk_percent is not None and risk_percent != "":
+        try:
+            pct = float(risk_percent)
+        except (TypeError, ValueError):
+            pct = None
+    pct_txt = f"{pct:g}" if pct is not None else "—"
+    amt_txt = round_funds(amt, decimals) if amt is not None else "—"
+    return f"{pct_txt}%≈{amt_txt}U"
+
+
 def assert_open_source_allowed(mode: str, source: str) -> Tuple[bool, str]:
     if not is_full_margin_mode(mode):
         return True, ""