[inureyes]

Summary

docs/turbo-kv-cache.md still described MLXCEL_PAGED_ATTENTION_NATIVE as a library/bench-only control, "not a server knob." That claim went stale when issue #899 made the fused v2 kernel the production decode path and turned this variable's force-off values into the server's kill switch, and the same claim was already corrected in docs/environment-variables.md by PR #1119.

What changed

• Rewrote the tail of the ### Measured payoff paragraph in docs/turbo-kv-cache.md to name both current consumers of MLXCEL_PAGED_ATTENTION_NATIVE: the library-only pooled entry point retired by perf(core): wire the pooled paged-attention decode entry point into the scheduler or retire it #710, and the server's pool-backed batched paged decode (resolve_dispatch_decision and resolve_paged_v2_dispatch in src/lib/mlxcel-core/src/layers.rs).
• Stated the server-side behavior concretely: force-off values are the Route production batched paged decode through the fused v2 kernel, retiring the gather-then-SDPA hot path #899 kill switch, and a force-on value pins v2 for every servable shape, bypassing the measured token floors.
• Kept the perf(core): wire the pooled paged-attention decode entry point into the scheduler or retire it #710 retirement as history rather than a current statement, matching the framing docs/environment-variables.md uses after PR docs: add the six paged-decode v2 variables and correct the NATIVE row #1119.
• Cross-linked docs/environment-variables.md#paged-decode-v2-variables and docs/CONTINUOUS_BATCHING.md#seeing-which-path-ran instead of duplicating the dispatch policy and log-line prose, and kept the existing ADR 0001 link.
• Left docs/adr/0001-paged-attention-gather-vs-fused-kernel.md and the History: clause in docs/environment-variables.md untouched, since both intentionally describe the past.

Test plan

• grep -rn "not a server" docs README.md only shows the ADR 0001 decision record and the two History: clauses (in docs/environment-variables.md and now docs/turbo-kv-cache.md), none asserting current behavior
• python3 scripts/ci/check_cross_repo_refs.py passes
• git diff --stat shows docs/turbo-kv-cache.md only, no code touched

Closes #1139