fix: Add 99% safety buffer for 100% position sizing
Problem: Bot trying to use exact 100% of collateral causes InsufficientCollateral
errors due to Drift's margin calculation including fees, slippage buffers, etc.
Example:
- Collateral: $85.55
- Bot tries: $85.55 (100%)
- Margin required: $85.58 (includes fees)
- Result: Insufficient by $0.03 → Rejected
Drift UI works because it automatically applies safety buffer internally.
Solution: When user configures 100% position size, apply 99% safety buffer
to leave room for fees and slippage calculations.
Code change (config/trading.ts calculateActualPositionSize):
- Check if configuredSize >= 100
- Use 99% (0.99) instead of 100% (1.0)
- Log warning about safety buffer application
Impact: Bot can now use 'full' collateral without InsufficientCollateral errors.
Position size: $85.55 × 99% = $84.69 (well within margin requirements)
Math proof (from user's Drift UI):
- Available: $85.55
- UI max: $1,282.57 (15x leverage)
- Bot now: $84.69 × 15 = $1,270.35 (safe margin)
7129cbfb8a