Sync on updated PostResponse plugins

[vMaroon]

The IGW has recently been updated with:

• Break PostResponse requestcontrol plugin into 3 separate plugins to add streamed request functionality kubernetes-sigs/gateway-api-inference-extension#1661

Which would fix a problem observed with the active-request-scorer when streaming is enabled, as pointed out here:

• Unexpected behavior of PostResponse plugins for streaming requests kubernetes-sigs/gateway-api-inference-extension#1483

To implement the fix (#376), we need to import these new plugins.

[vMaroon]

cc @nirrozenbaum @kfswain

[learner0810]

/assign

[learner0810]

The latest version of GAIE 1.0.2, does not include modifications to the PostResponse plugins. Should we wait for version 1.0.3 or start development immediately?

Due to GAIE's restructuring of the end-to-end test code, upgrading the GAIE version relied upon by llm-d-inference-scheduler caused errors in llm-d-inference-scheduler's end-to-end test code. This occurred because llm-d's e2e test code references GAIE's end-to-end code. Should we adapt based on GAIE's e2e code, or should we implement the code ourselves?

https://github.com/llm-d/llm-d-inference-scheduler/blob/main/test/e2e/utils_test.go#L24
https://github.com/kubernetes-sigs/gateway-api-inference-extension/pull/1515/files