feat: configure new route propagation benchmark tests

[missBerg]

What type of PR is this?

test: enhance benchmark suite with route propagation timing metrics

What this PR does / why we need it:

This PR enhances the Envoy Gateway benchmark testing suite by introducing route propagation timing measurements, providing critical visibility into configuration deployment performance.

Key Enhancements:

🔍 Route Propagation Timing Framework

• New timing metrics: Measures control plane time (route creation → RouteConditionAccepted=True), data plane time (acceptance → traffic flowing), and end-to-end deployment time
• Performance visibility: Provides operational insights into how quickly configuration changes take effect in production environments
• Scale correlation: Tracks timing vs route count for capacity planning and performance regression detection

📊 Enhanced Reporting

• Integrated timing tables: Benchmark reports now include dedicated route propagation metrics sections
• Comprehensive documentation: Added detailed ROUTE_PROPAGATION_METRICS.md with usage instructions, troubleshooting, and CI/CD integration examples
• Better test organization: Refactored benchmark suite architecture with improved type definitions and modular structure

🎯 Operational Value

• Configuration velocity insights: Understanding deployment timing for operational planning
• Performance baseline establishment: Foundation for monitoring control plane performance characteristics
• Troubleshooting support: Detailed timing breakdowns help identify bottlenecks in route propagation

Why We Need This:

1. Operational visibility: Understand how long configuration changes take to propagate, especially at scale
2. Performance monitoring: Establishes baseline metrics for detecting regressions in control plane performance
3. Capacity planning: Route count vs timing correlation helps with infrastructure sizing decisions

Which issue(s) this PR fixes: N/A

Release Notes: Yes

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 70.69%. Comparing base (e78e268) to head (ab05193). Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6334      +/-   ##
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+ Coverage   70.67%   70.69%   +0.01%     
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  Files         220      220              
  Lines       37003    37003              
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+ Hits        26153    26160       +7     
+ Misses       9312     9306       -6     
+ Partials     1538     1537       -1     

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[missBerg]

/retest

[arkodg]

thanks @missBerg !

hey @shawnh2 ptal

[missBerg]

/retest

[missBerg]

/retest

[missBerg]

/retest

[missBerg]

/retest

[missBerg]

/retest