Fix: List index bug in outlier detection, add error logging

Bug #1: Fixed IndexError in outlier_detection.py:256
- Missing enumerate() caused stale loop var to access beyond bounds
- Occurred when hard bounds filtered deals before IQR processing
- Added test reproducing exact scenario (21 deals → 8 filtered)

Bug #2: Added stack traces to all MCP tool error logs
- Added exc_info=True to 10 MCP tools' error handlers
- Improves debugging by logging full stack traces

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

nadlan_mcp/govmap/outlier_detection.py

@@ -253,7 +253,7 @@ def filter_deals_for_analysis(
         if metric == "price_per_sqm":
             values = [
                 deal.price_per_sqm
-                for deal in deals
+                for i, deal in enumerate(deals)
                 if deal.price_per_sqm is not None and not filters_to_remove[i]
             ]
             value_indices = [