core: zero?/pos?/every? to 00-syntax, char? to the overlay; fix rest/next over sets and maps

Round 4 of the seed shrink. zero?, pos?, every? move to the syntax tier
(empty? and the analyzer use them — raw def+fn* per the file constraint);
char? joins the tagged-value predicates in 20-coll. coll? stays seed: host
set? doesn't cover sorted sets (filed jolt-dpn) and the tag check from the
overlay would hit the sorted-coll get trap. pos? guards number? explicitly —
the staged recompile emits bare > as the native janet op, which orders
strings (zero? gets the same guard; spec rows lock both plus neg?).

The canonical every? seq-walks its coll, which exposed that rest/next over
sets, phms, struct maps and sorted colls fell into core-rest's indexed
fall-through and walked the wrapper table's INTERNAL fields — (next #{1 2})
was (nil nil), (clojure.set/subset?) broke. core-rest now seqs those
representations (branches placed AFTER the hot vector/lazy paths; the first
ordering cost seq-pipe 4x). Suite rises 4700 -> 4703; baseline 4660 -> 4695.

even?/odd? are back in the seed after the bench A/B: (filter even? ...) pays
an extra call layer per element through the overlay (seq-pipe 262 -> 1100ms).
They join the perf-wall list with the lazy hot fns.

test/integration/clojure-test-suite-test.janet

@@ -43,7 +43,10 @@
 # Raised 4004 -> 4034 / clean 66 -> 67 porting partition-all + repeatedly to the
 # overlay, which required fixing two leniencies (a char is not callable; take
 # validates its count) — correct beyond those fns, so the suite rose broadly.
-(def baseline-pass 4660)
+# Raised 4660 -> 4695 (observed 4703) after the seed-shrink rounds: rest/next
+# over sets/maps/sorted colls fixed (they walked the wrapper table's internal
+# fields), canonical halt-when/==/memfn. Margin covers rand-based suite jitter.
+(def baseline-pass 4695)
 # A file is "clean" when it ran with zero failures AND zero errors.
 (def baseline-clean-files 88)
 # Per-file wall-clock budget (seconds). Normal files finish in well under 1s, so