Run core.memoize's test suite on jolt

Shaking out clojure.core.memoize (207 assertions, 0 fail) cleared several
general gaps:

- deref/@ on a deftype or reify implementing clojure.lang.IDeref dispatches to
  its deref method (RetryingDelay / make-derefable).
- deftype mutable fields (^:unsynchronized-mutable / ^:volatile-mutable) are
  read live: a set! within a method is observed by a later read in the same
  invocation, not the entry-time capture. Needed for double-checked locking.
  Immutable fields stay let-bound. Field reads rewrite to (.-field inst) with
  lexical-shadow tracking.
- def metadata values are evaluated, like Clojure: ^{:k (f)} stores (f)'s
  result and ^{:af some-fn} the fn. :tag stays a literal hint.
- try dispatches catch clauses by class in order via the exception supertype
  hierarchy; a non-matching value re-throws, an untyped host condition is caught
  by a RuntimeException/Exception/Throwable clause. Previously the last clause
  won and the class was ignored.
- locking takes a real per-object monitor (recursive Chez mutex) now that
  futures/agents/threads share one heap; it was a no-op.
- supers/ancestors reflect a small modeled JVM interface hierarchy, so
  (ancestors (class f)) yields Runnable/Callable (core.memoize's arg check).
- AssertionError / Error constructors.

JOLT_FEATURES is gone from the docs: it isn't read anywhere on Chez, and the
reader already includes :clj in its default feature set. RFC 0002's
{:jolt :default} design was reverted in the reader; docs now match the code.

Raises the SCI floor 205 -> 210.

docs/rfc/0002-reader-conditional-features.md

@@ -1,9 +1,22 @@
 # RFC 0002 — Reader-Conditional Feature Set
 
-- **Status**: Accepted (implemented; measured)
+- **Status**: Superseded (2026-06-25) — jolt now includes `:clj` in the default
+  set; see the note below.
 - **Created**: 2026-06-10
 - **Spec**: `docs/spec/02-reader.md` §2.3 S18
 
+> **Update (2026-06-25).** The default set is now **`#{:jolt :clj :default}`** —
+> `:clj` is satisfied by default. The clj ecosystem's `.cljc` libraries gate
+> their host code behind `#?(:clj …)` with no `:jolt`/`:default` fallback, so
+> the conformance libraries (core.cache, core.match, tick, malli, …) only load
+> with `:clj` present; requiring an opt-in for each was friction with no payoff
+> once jolt's `clojure.lang.*`/`java.*` emulation was broad enough to run those
+> `:clj` branches. Matching is still by **clause order**, so a library can place
+> a `:jolt` branch first to override. There is no `JOLT_FEATURES` environment
+> variable; a loading context overrides the set at runtime with
+> `reader-features-set!`. The rest of this RFC is the original (reverted)
+> design.
+
 ## Summary
 
 jolt's reader-conditional feature set is **`#{:jolt :default}`**, matched in