chore: code review fixes + project cleanup

Code Review Fixes:
- trading_database.py: logger, f-string SQL, except:pass, bot_settings table
- drawdown_protection.py: persist pause state, float('inf') on DB error, Markdown fix
- position_monitor.py: mt5 alias, partial closes, UTC timezone, dynamic tolerance
- adaptive_rhythm_manager.py: implement get_volatility_level(), pytz→timezone, shutdown()
- trading_dashboard.py: fix time.sleep auto-refresh, st.rerun(), DB error handling
- trading_bot_gui.py: thread-safe GUI updates, scheduler guard, MT5_LOGIN constant
- performance_analysis.py: fix KeyError in export, profit factor formula, SQL filter
- performance_analysis_simple.py: datetime parsing, bin sorting, profit factor
- check_market_regime.py: DX div/zero, Wilder smoothing, UTC timestamp, try/finally
- check_system_status.py: remove duplicate cursor.execute
- Notebook: mt→mt5 (60 calls), fix calculate_position_size(self→), remove force-resume

Project Cleanup:
- Remove 6 tracked notebook backups (git is version control)
- Remove 21 one-shot notebook patch/fix/add scripts
- Remove 25 outdated fix-note and status markdown files
- Untrack runtime data files (trade JSONs, .pkl, .DS_Store) via git rm --cached
- Update .gitignore: trade data, ML artifacts, notebook backups

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -56,9 +56,19 @@ misc/
 temp/
 tmp/
 
-# Performance data (optional - keep template)
-# Uncomment if you don't want to track trade data
-# trade_performance_*.json
+# Runtime trade data & ML artifacts
+trade_performance_*.json
+demo_test_stats.json
+dynamic_thresholds.json
+equity_curve_history.json
+profitability_analysis.json
+signal_cache.json
+loss_protection_state.json
+performance_report.txt
+*.pkl
+
+# Notebook backups (Git ist die Versionsverwaltung)
+*_backup_*.ipynb
 
 # Streamlit cache
 .streamlit/