Chez Phase 3 inc 5b: reader collections + quote/deref/meta in jolt.reader

Ports list/vector/map literals and the quote family (' ` ~ ~@ @) + metadata (^)
to the portable Clojure reader. read-form now returns a [kind payload pos] control
triple (:form / :skip / :splice) instead of the Janet reader's :jolt/skip sentinel
FORMS — out-of-band control is collision-free and host-neutral (no tagged struct
to build or recognize). read-delimited dispatches the kinds; read-next-form skips
comments where a single datum is needed; read-map pairs k/v skipping trivia in
either slot. syntax-quote of a self-evaluating literal collapses at read time.

Four host constructors added to the contract (host_iface): form-make-list/vector/
map + form-sym-merge-meta (attach ^meta to a symbol). form-make-map reuses the
seed's reader-map (now public) for the source-order kv tracking. The portable
reader accumulates items in a jolt vector and the host builds its native form rep.

Gate: reader-parity 107/107 (lists/vectors/maps incl. nested + comments-in-coll,
quote/syntax-quote-collapse/unquote/deref, ^:dynamic/^Type/^{} meta). Full jpm gate
green (prelude cache pre-warmed — a cold cache races under the parallel gate when
the jolt-chez fingerprint changes; pre-existing, see new bead). jolt-sh1n.

test/chez/reader-parity.janet

@@ -79,5 +79,26 @@
 # characters
 (each i [`\a` `\Z` `\0` `\newline` `\tab` `\space` `\return` `\\` `\(` `\{` `\%` `A` `\o101`] (check i))
 
+# --- inc 5b: collections + quote/deref/meta -----------------------------------
+# lists
+(each i ["(1 2 3)" "(a b c)" "()" "(foo (bar baz) qux)" "(+ 1 (* 2 3))"] (check i))
+(check "(1 ; c\n 2 3)")     # comment inside a list
+# vectors
+(each i ["[1 2 3]" "[]" "[a [b c]]" "[1 [2 [3]]]" "[:a :b :c]"] (check i))
+# maps
+(each i ["{:a 1 :b 2}" "{}" "{:a {:b 1}}" "{:x [1 2] :y {:z 3}}" "{1 2 3 4}"] (check i))
+(check "{:a 1 ; c\n :b 2}")  # comment inside a map (key/value slots)
+# mixed / nested forms (real code shapes)
+(each i ["(defn f [x] (+ x 1))" "{:list (1 2) :vec [3 4]}" "(let [a 1 b 2] (+ a b))"] (check i))
+# quote / syntax-quote / unquote / deref
+(each i ["'foo" "'(1 2 3)" "''x" "'[a b]" "'{:a 1}"] (check i))
+(each i ["`foo" "`(a b c)" "`[x y]"] (check i))
+(check "`\"meow\"")          # syntax-quote of a literal collapses
+(each i ["~x" "~@xs" "@x" "@(atom 1)"] (check i))
+(check "`(a ~b ~@c)")
+# metadata
+(each i ["^:dynamic x" "^String s" "^:private foo" "^{:a 1} v" "^t/Ray r"] (check i))
+(check "(defn ^:private g [x] x)")
+
 (printf "\n%d/%d ok" (- total fails) total)
 (when (> fails 0) (os/exit 1))