[Data] Concurrency cap backpressure with tuning (Disabled) (#59519) EWMA_ALPHA Update EWMA_ALPHA from 0.2->0.1. This makes adjusting level to be more in-favor of limiting concurrency by being more sensitive to downstreaming queuing. K_DEV Update K_DEV from 2.0->1.0. This makes stddev to be more in-favor of limiting concurrency by being more sensitive to downstreaming queuing. cherry-pick of #59392

Cherry pick browser request validation improvements (#59045) Cherry pick #58553 #58648 #59042 --------- Signed-off-by: Richo Healey <richo@anyscale.com> Signed-off-by: Edward Oakes <ed.nmi.oakes@gmail.com> Co-authored-by: richo-anyscale <richo@anyscale.com> Co-authored-by: Lonnie Liu <95255098+aslonnie@users.noreply.github.com>

change version to 2.52.1 (#59049) for 2.52.1 release Signed-off-by: elliot-barn <elliot.barnwell@anyscale.com>

[core] Cherry pick token authentication UX improvements (#58831) Cherry pick: #58737 Signed-off-by: sampan <sampan@anyscale.com> Signed-off-by: Edward Oakes <ed.nmi.oakes@gmail.com> Co-authored-by: Sampan S Nayak <sampansnayak2@gmail.com> Co-authored-by: sampan <sampan@anyscale.com>

Fixes to tests (#58317) lint on code format and cherrypick #58215 --------- Signed-off-by: Lonnie Liu <lonnie@anyscale.com>

[core][cherry-pick] RDT NIXL Limitations + Throw Exception (#58159) ## Description Cherry-picking #58063 to throw an exception when trying to double send the same ref before gc because it can trigger a NIXL error. Also adding documentation for this. Signed-off-by: Dhyey Shah <dhyey2019@gmail.com> Signed-off-by: Qiaolin-Yu <liin1211@outlook.com> Signed-off-by: Qiaolin Yu <liin1211@outlook.com> Co-authored-by: Qiaolin Yu <liin1211@outlook.com> Co-authored-by: Stephanie Wang <smwang@cs.washington.edu>

[cherry-pick] [core] Fix deadlock when cancelling stale requests on i… …n-order actors (#57746) (#57768) ## Description Cherry picking #57746 Signed-off-by: dayshah <dhyey2019@gmail.com>

[DOC-127] Cherry-pick (#54254): MVP for OSS Ray labels (#57547) (cherry picked from commit 44a9732) Co-authored-by: Douglas Strodtman <douglas@anyscale.com>

2.49.2 version change (#56501) Signed-off-by: Lonnie Liu <lonnie@anyscale.com>

[data] Cherry pick data fixes for 2.49.1 (#56058) Cherry pick two fixes for ray data (from #55854 and #55926). --------- Signed-off-by: iamjustinhsu <jhsu@anyscale.com> Signed-off-by: Alexey Kudinkin <alexey.kudinkin@gmail.com> Signed-off-by: Matthew Owen <mowen@anyscale.com> Co-authored-by: iamjustinhsu <140442892+iamjustinhsu@users.noreply.github.com> Co-authored-by: Alexey Kudinkin <alexey.kudinkin@gmail.com>