Chez Phase 2 (inc G): lazy-seq bridge (make-lazy-seq / coll->cells)

The lazy-seq macro expands to (make-lazy-seq (fn* [] (coll->cells body)))
and lazy-cat to (concat (lazy-seq c) ...); both seed natives were nil on
the prelude, so every overlay fn built on lazy-seq — repeat/iterate/
cycle/dedupe/take-nth/keep/interpose/reductions/map-indexed/distinct/
interleave/tree-seq(->flatten)/partition-all/lazy-cat — hit apply-jolt-nil.

lazy-bridge.ss bridges to the cseq model: a jolt-lazyseq is a deferred
seq forced once by an extended jolt-seq; jolt-cons defers a lazyseq tail
so an infinite (repeat/iterate/cycle) stays lazy. A lazyseq is a new
value type, so the dispatchers that don't route through jolt-seq learn it
(sequential? for =/hash, plus count/empty?/nth/printers) or a raw
unrealized lazyseq escapes — the corpus compares (= [1 3 5] (take-nth …))
against it directly.

seq.ss: jolt-concat is now fully lazy (the rest isn't forced until the
first coll is exhausted), so a self-referential lazy-cat — fib =
(lazy-cat [0 1] (map + (rest fib) fib)) — no longer memoizes its tail as
empty by reading fib before its def binds.

Prelude parity 1837 -> 1886, 0 new divergences. Floor raised to 1886.

host/chez/rt.ss

@@ -206,3 +206,9 @@
 ;; through their :ops table). Loaded LAST — wraps the jrec-extended dispatchers
 ;; (records.ss), jolt-disj (transients.ss), and value-host-tags (records.ss).
 (load "host/chez/host-table.ss")
+
+;; lazy-seq bridge (jolt-dmw9, Phase 2): make-lazy-seq / coll->cells over the
+;; cseq model — unblocks every overlay fn built on the lazy-seq macro (repeat/
+;; iterate/cycle/dedupe/take-nth/keep/interpose/reductions/tree-seq/lazy-cat).
+;; Loaded LAST so %ls-seq captures the fully-extended (sorted-aware) jolt-seq.
+(load "host/chez/lazy-bridge.ss")