Chunk range/map/filter to match JVM Clojure

range, map, and filter were fully element-by-element lazy, so
(map f (range 1 50)) realized one element per first/nth where JVM
Clojure realizes a whole 32-element chunk. range is a chunked
LongRange on the JVM and map/filter are chunk-preserving, so the
observable side-effect timing differed.

Following clojure.lang.LongRange, ChunkedCons, ChunkBuffer and
core.clj, this adds a crest field to the cseq record and a
cseq-chunked constructor modeling ChunkedCons (a standalone chunk
pvec, an offset, and the after-chunk seq). The chunk accessors move
to seq.ss next to the representation they read. map/filter/remove
take a chunked branch when the source is chunked, realizing the whole
chunk and chunk-cons'ing it onto a lazy rest, so their output is
itself chunked and chained transforms each batch by 32. Bounded range
is now an eager chunked seq, and the reduce fast path flows through a
ChunkedCons rest. The chunk-buffer/chunk/chunk-cons builder API in
natives-array.ss now produces a real ChunkedCons.

Single-arg (range), multi-coll map, and plain lazy seqs stay
element-by-element, like the JVM.

Adds a lazy / chunking suite to the corpus that observes realization
timing via an atom counter: first over a chunked map realizes 32,
crossing a chunk boundary realizes 49, chained maps batch [32 32],
filter applies the predicate to the whole first block, and a plain
lazy seq still realizes one element at a time. Two cases that
documented the old over-laziness now assert the JVM value of 32 and
were dropped from the allowlist. certify against JVM Clojure 1.12.3
reports 0 new and 0 stale divergences.

host/chez/natives-meta.ss

@@ -50,7 +50,7 @@
     ;; original mutated it, so (with-meta xs {:k xs}) built a self-referential
     ;; cycle that loops *print-meta* printing.
     ((cseq? x) (make-cseq (cseq-head x) (cseq-tail x) (cseq-forced? x)
-                          (cseq-list? x) (cseq-cvec x) (cseq-ci x)))
+                          (cseq-list? x) (cseq-cvec x) (cseq-ci x) (cseq-crest x)))
     ((jolt-lazyseq? x) (make-jolt-lazyseq (jolt-lazyseq-thunk x) (jolt-lazyseq-val x)
                                           (jolt-lazyseq-realized? x)))
     (else x)))                          ; procedure