v1.0.0-rc.4

a list of PRs that are cherry picked into RC4:

CRD updates:

#1521

performance issues fixed in pickers:

#1523
#1514
#1528

helm chart fix:

#1522
#1540
#1542

bug fix in prefix when no request id header is supplied by the gateway:

#1490 (was on the original list but somehow missed, without this prefix cache won't work in bursty workload)

test flake fix, required for llm-d to use formal image of IGW:

#1534

** all the items in this list have been cherry picked successfully into the release branch.