Support for the aggression parameter within the LoadBalancerSettings configuration.

[xocodergit]

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Describe the feature request
Istio now supports the envoy slow_start_window parameters through the LoadBalancerSettings.warmupDurationSecs feature. In most cases, this configuration is sufficient for effective service warm-up. However, because of the lack of aggression parameter, there are certain scenarios where this mechanism may not yield the ideal result. For instance, applications with built-in caching mechanisms, where cache building is request-triggered, might experience a non-linear decrease in response latency as the cache becomes populated. In such cases, the initial performance drop due to cache build-up can be significant before it stabilizes to optimal response times. To achieve overall better performance, it is preferable to assign fewer requests during the initial phase of the application startup, then rapidly increase the volume of requests to regular levels once the cache has been built. This is precisely what the aggression parameter can do.

Describe alternatives you've considered
I've noticed the issue reported at #41039. While an EnvoyFilter patch can be used to adjust the aggression parameter, a more elegant solution would be to allow configuration directly within the DestinationRule.

Affected product area (please put an X in all that apply)

[ ] Ambient
[ ] Docs
[ ] Dual Stack
[ ] Installation
[x] Networking
[ ] Performance and Scalability
[ ] Extensions and Telemetry
[ ] Security
[ ] Test and Release
[x] User Experience
[ ] Developer Infrastructure

Affected features (please put an X in all that apply)

[ ] Multi Cluster
[ ] Virtual Machine
[ ] Multi Control Plane

Additional context

I'd like raise a PR to add support for "aggression" parameter :)