clojure.string toString coercion; some-fn/ifn? reference semantics; misc host gaps

The clojure.string case fns and searches now take any Object s through its
toString like the reference's ^CharSequence signatures ((upper-case :kw) is
":KW", (capitalize 1) is "1"); nil throws, and a nil substr in
starts-with?/ends-with? throws. some-fn re-ported with the reference
arities: (some-fn) is an arity error and a no-match result is the last
predicate's own falsy value (false, not nil). ifn? covers multimethods,
promises (which are now invocable — calling one delivers, via a cold-path
invoke-arm registry that costs the hot dispatch nothing), and deftypes
implementing IFn's invoke.

One structural find on the way: defmulti/defmethod deferred inside a fn
body (the deftest pattern) interned/resolved in whatever namespace was
current when they RAN, not the one they were written in — the macros now
bake their expansion ns and the setups honor it.

Also: Boolean/Integer/Double wrapper ctors, primitive TYPE statics
(Integer/TYPE etc.), .reduce on collections (IReduce), and Long/TYPE.

cts baseline 5857 -> 5904 pass, 58 -> 28 errors, 57 baselined namespaces —
the string cluster, some-fn, ifn-qmark, boolean-qmark, and reduce
namespaces are all fully clean. 7 JVM-certified corpus rows; spec entry.

host/chez/java/dot-forms.ss

@@ -60,6 +60,12 @@
     ;; branch and is mis-read as a missing :iterator key (nil). Some libraries
     ;; (e.g. malli's -vmap) iterate a map this way.
     ((string=? name "iterator") (list (make-jiterator (jolt-seq obj))))
+    ;; (.reduce coll f) / (.reduce coll f init): clojure.lang.IReduce — every
+    ;; persistent collection reduces itself on the JVM.
+    ((string=? name "reduce")
+     (list (if (pair? (cdr args))
+               (jolt-reduce (car args) (cadr args) obj)
+               (jolt-reduce (car args) obj))))
     (else #f)))
 
 ;; Universal object-methods: on a