Add statistical gating optimization (post-MVP enhancement)

[jonnyspicer]

Overview

Improve detection-to-track association with statistical gating, after basic radar-only association is working.

Priority Revision

DOWNGRADED from MVP Critical → Post-MVP Enhancement

Reason: Statistical gating is an optimization of existing association. The real MVP blocker is having any radar-only association (#20), not optimizing it.

Current State

• Basic Euclidean distance gating in Stone Soup tracker
• Single threshold-based approach

Target State (Post-MVP)

• Statistical gating methods (Chi-squared test)
• Configurable gating parameters for different scenarios
• Improved association quality with reduced false associations

Dependencies

• BLOCKED by Implement RadarOnlyAssociator for pure radar tracking #20 - Need basic radar-only association working first
• Should be completed after MVP radar-only functionality is proven

Benefits

• Reduced false associations through statistical validation
• Better track quality with appropriate gating
• Foundation for more sophisticated association

MVP Scope Limitations

• NOT needed for MVP - basic association is sufficient
• Focus first on getting radar-only operation working
• Optimize later once core functionality is proven

Note: This is valuable but not blocking. Getting radar-only tracking working at all is the MVP priority.