Chez Phase 1 (increment 3b): seq tier + dynamic IFn dispatch on the Chez RT

Brings up the seq layer on the Chez runtime. host/chez/seq.ss adds one
lazy-capable node (cseq) that models Clojure's list, cons, and lazy seq -
all print as (...), all sequential-= to each other and to vectors. seq
coerces any seqable (vector/map/set/string/list/seq/nil) to a cseq or nil;
the empty seq is a distinct value printing () (rest of a 1-elem coll is ()
not nil, seq of empty is nil). Leaf ops: first/rest/next/seq/cons/list,
reverse/last, map/filter/remove/reduce/into, range/take/drop/concat/apply,
keys/vals, plus nth/peek/pop extended over seqs. map/filter/reduce apply
their fn arg through jolt-invoke, so a procedure, keyword, or collection all
work as the fn.

Dynamic IFn dispatch: a keyword/vector/coll held in a local (let binding or
fn param) and called as a fn now routes through the jolt-invoke fallback
(procedure? -> apply; keyword/coll -> lookup). The emitter only routes a
:local callee that isn't a known procedure - a named fn's self-recursion
name stays a direct call, so the fib hot path is untouched. Closes the 3
ex-known IFn divergences.

emit.janet: seq/pred ops added to native-ops with arity gates; value-position
clojure.core refs resolve to the RT procedure (native-ops names one for each),
with +/-/*// routed to flonum-coercing wrappers so higher-order arithmetic
((reduce + [])) keeps the all-double model. values.ss: cross-type sequential
=/hash so a vector and a list of the same elements are jolt= and hash alike.
rt.ss: printer learns seqs; top-level nil prints as the empty string (jolt -e
str-style). Fixed latent bug: (conj nil ...) now builds a list, not a vector.

Gates: emit-test 69/69 (fib/mandelbrot/collections/seq/IFn parity vs the jolt
oracle, fib(30) ~24ms unchanged). Subset probe 433/436 -> 595/595 compiled,
0 divergences (was 3 known), 2060/2655 out of subset. Full run-tests green
(125 files, conformance + suites included).

test/chez/README.md

@@ -48,14 +48,16 @@ compile-time signal) and are counted "out of subset", not as divergences.
 
     JOLT_CHEZ_CORPUS=1 janet test/chez/run-corpus-chez.janet
 
-Baseline after inc 3a (persistent collections, jolt-wgbz): **433/436 compiled
-cases pass**, 3 known divergences, 0 NEW; 2219/2655 out of subset (await the seq
-tier + core on Chez). The 3 known divergences are dynamic IFn dispatch — a
-keyword/vector held in a LOCAL and called as a fn (`(let [k :a] (k m))`); the
-STATIC literal forms (`(:a m)`, `({:a 1} :a)`) are supported. They're
-allowlisted in the probe; it exits non-zero on a NEW divergence.
+Baseline after inc 3b (seq tier + dynamic IFn, jolt-5pso): **595/595 compiled
+cases pass**, 0 divergences; 2060/2655 out of subset (await clojure.core on Chez).
+The seq tier brought up a list/lazy-seq type with first/rest/next/seq/cons/list,
+map/filter/reduce/into/remove, range/take/drop/concat/apply, keys/vals, and
+nth/peek/pop over seqs; dynamic IFn dispatch (a keyword/vector/coll held in a
+local and called as a fn) now routes through the `jolt-invoke` fallback, closing
+the 3 ex-known divergences. The probe exits non-zero on any NEW divergence.
 
-(Prior, inc 2 baseline: 182/182 compiled, 0 divergences, 2473 out of subset.)
+(Prior, inc 3a: 433/436 compiled, 3 known IFn divergences, 2219 out of subset.
+Inc 2: 182/182 compiled, 0 divergences, 2473 out of subset.)
 
 It's a slow report (a Chez subprocess per case), so it's gated behind
 `JOLT_CHEZ_CORPUS` out of the default suite, like the benches.

test/chez/emit-test.janet

@@ -121,6 +121,70 @@
     (ok (string "coll: " src) (and (= code 0) (= out want))
         (string "chez=" out " janet=" want " | " err))))
 
+# 3d) dynamic IFn dispatch (inc 3b): a keyword/vector/coll held in a LOCAL (let
+#   binding or fn param) and called as a fn. The 3 ex-known-divergences. The
+#   callee is a :local that's NOT the fn's self-name, so emit routes it through
+#   the jolt-invoke fallback (procedure? -> apply; keyword/coll -> lookup).
+(each [src want] [["(let [v [10 20 30]] (v 1))" "20"]
+                  ["(let [k :a] (k {:a 7}))" "7"]
+                  ["((fn [f] (f {:a 1})) :a)" "1"]]
+  (let [[code out err] (d/run-on-chez ctx src)]
+    (ok (string "ifn: " src) (and (= code 0) (= out want))
+        (string "chez=" out " want=" want " | " err))))
+
+# 3e) seq tier (inc 3b): jolt list type, first/rest/next/seq/cons/list, lazy-seq
+#   (range/take over an infinite seq), map/filter/reduce/into/remove, keys/vals.
+#   Lists and lazy seqs print as (...) and are sequential-= to vectors. Ordered
+#   shapes -> printed-form parity vs the CLI oracle.
+(each src ["(first [1 2 3])"
+           "(rest [1 2 3])"
+           "(rest [1])"
+           "(rest [])"
+           "(next [1 2 3])"
+           "(next [1])"
+           "(cons 0 [1 2 3])"
+           "(cons 1 nil)"
+           "(list 1 2 3)"
+           "(list)"
+           "(seq [])"
+           "(conj (list 2 3) 1)"
+           "(conj nil 1 2)"
+           "(map inc [1 2 3])"
+           "(map + [1 2 3] [10 20 30])"
+           "(map :a [{:a 1} {:a 2}])"
+           "(filter even? [1 2 3 4])"
+           "(remove even? [1 2 3 4])"
+           "(reduce + 0 [1 2 3])"
+           "(reduce + [1 2 3])"
+           "(reduce + (map inc (range 4)))"
+           "(into [] [1 2 3])"
+           "(into [1] (list 2 3))"
+           "(take 3 (range))"
+           "(reverse [1 2 3])"
+           "(apply + [1 2 3])"
+           "(count (map inc [1 2 3]))"]
+  (let [[code out err] (d/run-on-chez ctx src)
+        want (cli-oracle src)]
+    (ok (string "seq: " src) (and (= code 0) (= out want))
+        (string "chez=" out " janet=" want " | " err))))
+
+# 3f) seq tier — unordered / cross-type, equality-wrapped (prints true/false):
+#   keys/vals order is HAMT order, into-map / into-set unordered; sequential =
+#   across vector and list.
+(each src ["(= 2 (count (keys {:a 1 :b 2})))"
+           "(= 3 (reduce + (vals {:a 1 :b 2})))"
+           "(= {:a 1 :b 2} (into {} [[:a 1] [:b 2]]))"
+           "(= #{1 2 3} (into #{} [1 2 3]))"
+           "(= [1 2 3] (list 1 2 3))"
+           "(= [1 2 3] (map inc [0 1 2]))"
+           # jolt returns a vector for (seq vec) / bounded (range); Chez returns a
+           # Clojure-canonical lazy seq. Values are sequential-=, printed forms differ.
+           "(= [1 2 3] (seq [1 2 3]))"
+           "(= [0 1 2 3 4] (range 5))"]
+  (let [[code out err] (d/run-on-chez ctx src)]
+    (ok (string "seq=: " src) (and (= code 0) (= out "true"))
+        (string "chez=" out " | " err))))
+
 # 4) perf signal: emitted fib(30) in-Scheme timing (excludes Chez startup), to
 #    track against the spike ceiling (hand-Scheme fib ~5ms). Informational — the
 #    jolt-truthy? wrapper (~3x) and flonum modeling are known Phase-4 levers.

test/chez/run-corpus-chez.janet

@@ -28,15 +28,13 @@
     corpus))
 
 # Known subset divergences: cases that compile but need a feature beyond the
-# current increment. Dynamic IFn dispatch — a keyword/vector held in a LOCAL or
-# var then called as a fn ((let [k :a] (k m))) — is runtime dispatch on the
-# invoke mechanism, deferred to the IFn/protocol increment. The STATIC literal
-# forms ((:a m), ({:a 1} :a)) ARE supported. Allowlisted by label; the gate fails
-# only on a NEW divergence.
+# current increment. None as of inc 3b — dynamic IFn dispatch (a keyword/vector
+# held in a LOCAL then called as a fn, (let [k :a] (k m))) now routes through the
+# jolt-invoke fallback, and the seq tier closed the rest. Add a label here if a
+# future increment surfaces a case that compiles but needs deferred semantics;
+# the gate fails only on a NEW (un-allowlisted) divergence.
 (def known-divergences
-  {"param holding a keyword (IFn leftover)" true
-   "vector-in-local as fn" true
-   "keyword-in-local as fn" true})
+  {})
 
 (def ctx (d/make-ctx))
 (var compiled 0) (var pass 0) (var out-of-subset 0)