deftype/record: clojure.lang collection interfaces + protocol identity

Running clojure.core.match (a macro-heavy library that builds its compiler out
of deftypes implementing clojure.lang interfaces) shook out a cluster of general
gaps. Its own suite goes from not-loading to 111/115 assertions.

- deftype/defrecord implementing a clojure.lang collection interface now drives
  the core fns: Indexed -> nth, Counted -> count, Associative -> assoc, ILookup
  -> get/valAt (non-field keys only, so a method's own field bindings don't
  recurse), ISeq -> seq/first/rest, IPersistentCollection -> conj, IFn -> the
  value is callable. A jrec is still a map of fields by default; the interface
  method wins when declared.

- Multi-arity inline methods are grouped into one fn (a type with (nth [_ i]) and
  (nth [_ i x]) kept only the last before). Built as data, not a nested
  syntax-quote, so a `(= ~ocr ~l) method body keeps its unquotes.

- instance?/satisfies? recognize a protocol a type implements, including a MARKER
  protocol with no methods (core.match's IPseudoPattern) — deftype/defrecord now
  record protocol satisfaction even with zero methods. Added ILookup/Indexed/
  Counted to the instance? taxonomy for the built-in collections.

- Syntax-quote: a fully-qualified class name (clojure.lang.ILookup) stays bare
  instead of being namespace-qualified; (unquote x) is detected in a lazy seq
  (a macro that builds its template with map, e.g. deftype's rewrite-set).

- clojure.set union/intersection/difference are variadic (& sets) + union 0-arity.
- java map view methods: keySet/values/entrySet/size/isEmpty.
- deprecated java.util.Date getters (getYear/getMonth/...) + the multi-arg
  (Date. year-1900 month0 date hrs min) constructor.

Seed change (deftype/defrecord macros + clojure.set) -> re-minted; the rest are
runtime. 11 JVM-certified corpus rows; make test + shakesmoke green.

host/chez/host-contract.ss

@@ -248,8 +248,12 @@
 
 (define (hc-sym nm) (jolt-symbol #f nm))
 ;; is `x` a non-empty list FORM whose head is the unqualified symbol `nm`?
+;; Detect a (unquote …) / (unquote-splicing …) form in a syntax-quote template.
+;; Any seq counts, not just a proper list: a macro that builds the template with
+;; map/for (e.g. deftype's rewrite-set) yields a LAZY seq, and its ~unquotes must
+;; still be recognized.
 (define (hc-head-is? x nm)
-  (and (cseq? x) (cseq-list? x)
+  (and (cseq? x)
        (let ((h (seq-first x)))
          (and (symbol-t? h) (jolt-nil? (hc-sym-ns h)) (string=? (symbol-t-name h) nm)))))
 (define (hc-second x) (seq-first (jolt-seq (seq-more x))))
@@ -266,6 +270,10 @@
                  (hashtable-set! gsmap nm g) g)))
           ((hc-special-symbol? nm) form)               ; special form: leave bare
           ((hc-interop-head? nm) form)                 ; interop (.method / Class. / .-field): bare
+          ;; a fully-qualified class name (java.util.Map, clojure.lang.ILookup) is
+          ;; a class token, not a var to namespace-qualify — leave it bare, as
+          ;; Clojure's syntax-quote resolves it to the class.
+          ((hc-fq-class-name? nm) form)
           ((var-cell-lookup "clojure.core" nm) (jolt-symbol "clojure.core" nm))
           ;; a name referred into the compile ns (:require :refer / :use :only)
           ;; qualifies to its SOURCE ns, not the compile ns — so a macro that