perf: Extend WindowTopN to support RANK

[SubhamSinghal]

Which issue does this PR close?

• Related to Optimize "per partition" top-k : ROW_NUMBER < 5 / TopK #6899 (DENSE_RANK to follow in a separate PR will close it).

Rationale for this change

PR #21479 introduced WindowTopN for ROW_NUMBER only; RANK and DENSE_RANK were explicitly out of scope. This PR extends the rule to RANK, replacing the full sort under Filter(rk≤K) → Window(RANK) → Sort with a per-partition heap-of-K plus a boundary-tie buffer.

What changes are included in this PR?

• datafusion/physical-plan/src/topk/mod.rs — new pub(crate) struct PartitionedTopKRank (sibling of
  PartitionedTopK from perf: share encoder/reservation across PartitionedTopKExec partition … #23096) with per-partition RankPartitionState { TopKHeap, Vec<TieEntry> }.
• datafusion/physical-plan/src/sorts/partitioned_topk.rs — WindowFnKind enum (RowNumber / Rank).
  do_partitioned_topk dispatches on fn_kind to PartitionedTopK::try_new or PartitionedTopKRank::try_new;
• datafusion/physical-optimizer/src/window_topn.rs — is_row_number → supported_window_fn(expr) -> Option<WindowFnKind>; empty-order_by guard for RANK; WindowFnKind plumbed through PartitionedTopKExec::try_new.
• datafusion/sqllogictest/test_files/window_topn.slt — RANK SLT cases: basic, strict (<), flipped (>= / >),
  boundary ties, ties spanning ob values, empty-ORDER BY (rule must NOT fire), mixed window functions, ASC/DESC × NULLS FIRST/LAST, QUALIFY.
• datafusion/core/tests/physical_optimizer/window_topn.rs — 6 new RANK rule unit tests covering predicate
  matching, partition-by/order-by guards, dense_rank skip.
• benchmarks/queries/h2o/window.sql — six new RANK queries (Q14–Q17, Q22, Q23) covering partition counts from ~100 to ~100K, low and heavy tie densities.

h2o window benchmark, 10M-row large table, RANK top-2, 3-iteration average. Toggle via DATAFUSION_OPTIMIZER_ENABLE_WINDOW_TOPN.

Variant	Partitions	OFF (rule disabled)	ON (rule enabled)	Δ
RANK low ties (id3 % 100)	~100	305 ms	107 ms	2.84× faster ✓
RANK low ties (id3 % 1000)	~1K	263 ms	120 ms	2.19× faster ✓
RANK heavy ties (id3 % 1000, v2 % 10 OB)	~1K	282 ms	125 ms	2.25× faster ✓
RANK low ties (id2)	~10K	363 ms	140 ms	2.59× faster ✓
RANK heavy ties (id2, v2 % 10 OB)	~10K	291 ms	143 ms	2.04× faster ✓
RANK low ties (id3 % 100K)	~100K	241 ms	422 ms	1.75× slower

Are these changes tested?

Yes:

• cargo test -p datafusion-physical-plan --lib — 1455 passed
• cargo test -p datafusion-physical-optimizer --lib — 27 passed
• cargo test -p datafusion --test core_integration physical_optimizer::window_topn:: — 13 passed (7 ROW_NUMBER + 6 RANK)
• cargo test --test sqllogictests -- window_topn — passed

Are there any user-facing changes?

The existing optimizer.enable_window_topn config flag (default false) now also covers RANK queries. No public API additions

[SubhamSinghal]

@kumarUjjawal @2010YOUY01 will you be able to review this PR.

[comphead]

might be related #23021

[github-actions]

Thank you for opening this pull request!

Reviewer note: cargo-semver-checks reported the current version number is not SemVer-compatible with the changes in this pull request (compared against the base branch).

Details

     Cloning apache/main
    Building datafusion v54.0.0 (current)
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     Summary no semver update required
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    Building datafusion-physical-optimizer v54.0.0 (current)
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    Checking datafusion-physical-optimizer v54.0.0 -> v54.0.0 (no change; assume patch)
     Checked [   0.118s] 223 checks: 223 pass, 30 skip
     Summary no semver update required
    Finished [  84.160s] datafusion-physical-optimizer
    Building datafusion-physical-plan v54.0.0 (current)
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      Parsed [   0.134s] (baseline)
    Checking datafusion-physical-plan v54.0.0 -> v54.0.0 (no change; assume patch)
     Checked [   0.607s] 223 checks: 222 pass, 1 fail, 0 warn, 30 skip

--- failure method_parameter_count_changed: pub method parameter count changed ---

Description:
A publicly-visible method now takes a different number of parameters, not counting the receiver (self) parameter.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#fn-change-arity
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.48.0/src/lints/method_parameter_count_changed.ron

Failed in:
  datafusion_physical_plan::sorts::partitioned_topk::PartitionedTopKExec::try_new takes 4 parameters in /home/runner/work/datafusion/datafusion/target/semver-checks/git-apache_main/24b9a8b1b9103b5df7d3ca5afd4287d7de221a0d/datafusion/physical-plan/src/sorts/partitioned_topk.rs:196, but now takes 5 parameters in /home/runner/work/datafusion/datafusion/datafusion/physical-plan/src/sorts/partitioned_topk.rs:225

     Summary semver requires new major version: 1 major and 0 minor checks failed
    Finished [  79.358s] datafusion-physical-plan
    Building datafusion-sqllogictest v54.0.0 (current)
       Built [ 185.470s] (current)
     Parsing datafusion-sqllogictest v54.0.0 (current)
      Parsed [   0.026s] (current)
    Building datafusion-sqllogictest v54.0.0 (baseline)
       Built [ 182.375s] (baseline)
     Parsing datafusion-sqllogictest v54.0.0 (baseline)
      Parsed [   0.023s] (baseline)
    Checking datafusion-sqllogictest v54.0.0 -> v54.0.0 (no change; assume patch)
     Checked [   0.083s] 223 checks: 223 pass, 30 skip
     Summary no semver update required
    Finished [ 371.586s] datafusion-sqllogictest