Fix conformance gaps: exception types, byte/getBytes, host classes

Shake-out from the conformance-library sweep. Host-side fixes (runtime .ss,
no re-mint) plus one analyzer change (re-minted):

- Exception fidelity: ex-info and host-constructed throwables (RuntimeException.
  etc.) now carry their JVM class, so (class e), instance? across the exception
  hierarchy, .getMessage, and clojure.test thrown?/thrown-with-msg? all work.
- .getBytes returns a seqable/countable byte-array and honors UTF-16/UTF-32;
  String. decodes them. ->bytevector accepts byte-arrays (Base64).
- Universal .getClass / .toString / .indexOf / .lastIndexOf on any value/seq.
- record? uses the host jrec? predicate (the old (get x :jolt/deftype) crashed
  on a sorted-map by invoking its comparator).
- extend-protocol to abstract host types (clojure.lang.Fn/IFn/APersistentVector,
  java.net.URI) dispatches.
- New host classes: clojure.lang.PersistentQueue, java.util.ArrayList,
  java.net.URI, java.io.File / java.util.UUID ctors, Double/Float ctors+statics,
  regex instance? Pattern, System/setProperty.
- *assert* / *print-readably* are real settable/bindable vars.
- (symbol "ns/name") splits the namespace at the last slash.
- letfn fn params desugar destructuring (analyzer; re-minted).

unit.edn gains exinfo/hostobj/queue/hostctor/destructure regression rows.

host/chez/dot-forms.ss

@@ -71,6 +71,9 @@
                       (substring method-name 1 (string-length method-name))
                       method-name)))
       (cond
+        ;; (.getClass x) universal — the class token for any value, before the
+        ;; collection/map field-lookup arms below would read it as a missing key.
+        ((string=? method-name "getClass") (jolt-class obj))
         ;; collection interop first (entry count / seq / nth / get / containsKey).
         ((and (dot-coll? obj) (dot-coll-method obj mname rest))
          => (lambda (box) (car box)))