Fix general divergences surfaced by clojure-test-suite

Five fixes shaken out by running jank-lang/clojure-test-suite:

- = short-circuits on identity like Util.equiv's k1 == k2, so (= s s) on an
  infinite lazy seq answers true instead of walking forever. Numbers keep the
  exactness-aware arm ((= ##NaN ##NaN) stays false like the JVM's).
- Calling a non-fn names the operator's CLASS in the ClassCastException, like
  the JVM — never the value, whose printed form may be unbounded: ((range))
  must throw, not hang rendering an infinite seq.
- realized? on a seq cell answers by its forced flag (the rest of a realized
  lazy chain is a cseq under jolt's seq model), and the overlay's unsupported-
  type error names the class, not the (possibly infinite) value.
- clojure.test/is dispatches a REGISTERED assert-expr method before its by-name
  inline paths, like clojure.test where the built-ins are just pre-registered
  methods — so an alias-qualified p/thrown? (the suite's portability helper)
  isn't captured by the built-in thrown? path, which read its body as a class.
- clojure.test tracks tests and fixtures per namespace: deftest records its
  defining ns, use-fixtures registers under the calling ns (no more cross-ns
  clobbering), (run-tests 'ns ...) runs only those namespaces like clojure.test,
  and each run-tests call prints/returns its own summary (global counters stay
  cumulative for the n-pass/n-fail harness API).

Re-mint (20-coll.clj is seed; prelude only). +2 JVM-certified corpus rows;
the clojure-test fixture pins the alias-qualified assert-expr, per-call
summaries, and ns filtering.

host/chez/post-prelude.ss

@@ -63,6 +63,12 @@
         ;; a lazy-seq carries its own realized? flag (lazy-bridge.ss). The overlay
         ;; realized? reads :jolt/type and throws on a jolt-lazyseq record.
         ((jolt-lazyseq? x) (jolt-lazyseq-realized? x))
+        ;; a seq cell answers by its forced flag: the rest of a realized lazy
+        ;; chain is a cseq under jolt's seq model, and (realized? (rest s)) after
+        ;; a next must be true like the JVM's realized LazySeq — never a throw
+        ;; whose message renders the (possibly infinite) seq.
+        ((cseq? x) (if (cseq-forced? x) #t #f))
+        ((empty-list-t? x) #t)
         (else (jolt-invoke overlay-realized? x))))))
 ;; clojure.edn/read over a reader: drain the jhost reader, then read through the
 ;; overlay read-string so the opts map (:readers/:default/:eof) is honored.