docs: update copilot-instructions for ATR trailing + dynamic runner% + rate limits

Updated .github/copilot-instructions.md to reflect recent system improvements:

**ATR-Based Trailing Stop:**
- Dynamic trailing calculation formula documented
- Configurable runner % (default 25%, adjustable via TAKE_PROFIT_1_SIZE_PERCENT)
- All UI displays now dynamically calculate runner% as 100 - TP1_SIZE
- Removed hardcoded '25%' references, replaced with dynamic language

**Rate Limit Monitoring:**
- NEW Section #4: Rate Limit Monitoring
- Exponential backoff mechanism (2s→4s→8s)
- Database logging (3 event types: hit/recovered/exhausted)
- Analytics endpoint for monitoring
- Links to RATE_LIMIT_MONITORING.md for SQL queries

**Section Renumbering:**
- Old Section #4 (Order Placement) → Section #5
- Old Section #5 (Database) → Section #6
- Maintains logical flow and consistency

**Updated References:**
- Exit Strategy: Dynamic runner% description
- Position Manager: ATR trailing formula + on-chain sync notes
- Common Pitfalls: Dynamic runner % configuration notes
- Roadmap: Phase 5 shows configurable runner with formula

All documentation now accurately reflects user's 70/30 TP1/Runner split
and recent infrastructure improvements (ATR trailing, rate limits).

Related: settings UI updated in previous commit (app/settings/page.tsx)

.env

@@ -97,7 +97,7 @@ TAKE_PROFIT_1_PERCENT=0.4
 
 # Take Profit 1 Size: What % of position to close at TP1
 # Example: 50 = close 50% of position
-TAKE_PROFIT_1_SIZE_PERCENT=75
+TAKE_PROFIT_1_SIZE_PERCENT=70
 
 # Take Profit 2: Close remaining 50% at this profit level
 # Example: +1.5% on 10x = +15% account gain