chore: untrack paper_trades runtime data + report per anno/mercato

- data/paper_trades/ rimosso dal tracking (dati runtime, gitignored)
- scripts/analysis/yearly_market_report.py: accuracy/trades/PnL per anno×mercato

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -16,3 +16,4 @@ data/processed/
 *.pt
 *.pth
 notebooks/.ipynb_checkpoints/
+data/paper_trades/