Chez Phase 2 (inc Q): Java class statics + constructors (jolt-avt6)

Lower host class interop on the Chez back end. The analyzer now turns a
non-var qualified ref `Class/member` into a :host-static node and a
`(Class. ...)` / `(new Class ...)` form into a :host-new node (ir.clj
gains both, with walker support). The Janet back end punts both to the
interpreter, so its behavior is unchanged (verified: dot-form, `..`
threading, shadowed `new`, and all interop still resolve via fallback).

The Chez emit lowers a value ref to host-static-ref, a call head to
host-static-call, and a constructor to host-new. host/chez/host-static.ss
is the runtime registry these resolve against — the Chez port of the
seed's class-statics / class-ctors / tagged-methods (java_base.janet +
host_io.janet), restricted to the java.lang/util/net/io surface portable
cljc code calls: Math, System (getenv/getProperty/exit/currentTimeMillis),
Long, Integer, Boolean, Character, String, Thread, Class, Pattern
(compile/quote/MULTILINE), URLEncoder/Decoder, Base64, the Number method
surface (byteValue/intValue/...), plus the StringBuilder, StringWriter,
StringReader, PushbackReader, HashMap, StringTokenizer, BigInteger,
String, MapEntry, and exception constructors. Constructed objects are
jhost records dispatched through record-method-dispatch.

Also: emit now evaluates collection-literal elements left-to-right
(emit-ordered) — Chez evaluates call args right-to-left, which had been
swapping side-effecting elements in [(read r) (read r)] and map literals.
This un-allowlisted the 6 eval-order corpus cases (the read-line trio +
the three map-construction cases). Removed `.write` from the
jolt-host-call fast-path so a StringWriter routes through dispatch.

java.time formatting, edn/read-over-readers, and slurp/with-open over
readers are deferred to a follow-up.

Corpus parity 2078 -> 2134 (floor raised), 0 new divergences; the
print-method builtin-override case is allowlisted (same multimethod gap,
newly reachable now that StringWriter constructs). emit-test 326/326,
_javastatic 51/51, conformance 355x3, full jpm test green.

host/chez/rt.ss

@@ -271,3 +271,9 @@
 ;; a string target. After regex.ss (jolt-re-pattern/regex-t-irx) + records.ss
 ;; (which references jolt-string-method).
 (load "host/chez/natives-str.ss")
+
+;; host class statics + constructors (jolt-avt6, Phase 2): host-static-ref/
+;; host-static-call/host-new + the jhost method registry. Loads LAST — it extends
+;; record-method-dispatch (records.ss) and reuses natives-str helpers (str-trim,
+;; ascii-string-down, re-split, str-split-drop-trailing) + the regex-t accessors.
+(load "host/chez/host-static.ss")