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

simon/jolt

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.

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