fix(prompts): correct risk_usd formula - remove duplicate leverage multiplication

## Problem (Issue #592)
risk_usd formula incorrectly multiplies leverage twice:
- Incorrect: risk_usd = |Entry - Stop| × Position Size × Leverage ❌
This causes AI to calculate risk as 10x (or leverage倍) higher than actual.
## Root Cause
Position Size already includes leverage effect:
- Position Size (coins) = position_size_usd / price
- position_size_usd = margin × leverage
- Therefore: Position Size = (margin × leverage) / price
Multiplying leverage again amplifies risk calculation by "leverage" times.
## Example
Scenario: $100 margin, 10x leverage, 0.02 BTC position, $500 stop distance
**Correct calculation:**
risk_usd = $500 × 0.02 = $10 ✅
Risk % = 10% of margin (reasonable)
**Incorrect calculation (current):**
risk_usd = $500 × 0.02 × 10 = $100 ❌
Risk % = 100% of margin (completely wrong!)
## Impact
- AI miscalculates risk as "leverage" times higher
- May refuse valid trades thinking risk is too high
- Risk control logic becomes ineffective
- Potential for position sizing errors
## Solution
Correct formula: risk_usd = |Entry - Stop| × Position Size (coins)
Added warnings:
- CN: ⚠️ 不要再乘杠杆：仓位数量已包含杠杆效应
- EN: ⚠️ Do NOT multiply by leverage: Position Size already includes leverage effect
## Modified Files
- prompts/adaptive.txt (line 404)
- prompts/nof1.txt (line 104)
Closes #592

prompts/adaptive.txt

@@ -401,7 +401,8 @@
    - >95: 风险预算 2.5%（谨慎使用，警惕过度自信）
 
 5. **risk_usd** (风险金额)
-   - 计算公式: |入场价 - 止损价| × 仓位数量 × 杠杆
+   - 计算公式: |入场价 - 止损价| × 仓位数量
+   - ⚠️ **不要再乘杠杆**：仓位数量 = position_size_usd / 价格，已包含杠杆效应
    - 必须 ≤ 账户净值 × 风险预算（1.5-2.5%）
 
 6. **slippage_buffer** (滑点缓冲 - V5.5.1 新增)

prompts/nof1.txt

@@ -101,7 +101,8 @@ For EVERY trade decision, you MUST specify:
    - 80-100: Very high confidence (use cautiously, beware overconfidence)
 
 5. **risk_usd** (float): Dollar amount at risk (distance from entry to stop loss)
-   - Calculate as: |Entry Price - Stop Loss| × Position Size × Leverage
+   - Calculate as: |Entry Price - Stop Loss| × Position Size (in coins)
+   - ⚠️ **Do NOT multiply by leverage**: Position Size already includes leverage effect
 
 
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