fd subsystem: instance? name-boundary + ~ reads as clojure.core/unquote

Two general fixes that clear core.logic's finite-domain -difference, safefd, and
the defne quoted-list patterns (form->ast), taking the suite to 532/5/0.

- instance? on a deftype matched a simple type name against the qualified tag by
  raw string suffix, so "a.b.MultiIntervalFD" tested true for IntervalFD. The
  suffix must land on a "." boundary. core.logic's fd dispatches on
  (interval? x) = (instance? IntervalFD x), and a MultiIntervalFD wrongly counted
  as an interval, so -difference/safefd computed the wrong set.
- the reader reads ~ / ~@ as clojure.core/unquote(-splicing), like the JVM reader,
  instead of a bare unquote. Code that inspects quoted pattern/template data —
  core.logic's defne checks (= f 'clojure.core/unquote) — now sees the symbol it
  expects, so '(fn ~args . ~body) patterns compile. hc-head-is? accepts the
  qualified head in syntax-quote lowering; the value-preserving change leaves the
  minted seed byte-identical.

corpus.edn: 2 JVM-certified unquote rows. unit.edn: two reader rows updated to the
qualified unquote. make test + shakesmoke green, 0 new divergences, self-host holds.

host/chez/host-contract.ss

@@ -298,10 +298,15 @@
 ;; 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.
+;; head symbol matches name nm, bare or clojure.core-qualified — the reader
+;; produces clojure.core/unquote(-splicing) for ~/~@ (JVM parity), and this is
+;; only used to spot those heads in syntax-quote templates.
 (define (hc-head-is? x nm)
   (and (cseq? x)
        (let ((h (seq-first x)))
-         (and (symbol-t? h) (jolt-nil? (hc-sym-ns h)) (string=? (symbol-t-name h) nm)))))
+         (and (symbol-t? h) (string=? (symbol-t-name h) nm)
+              (let ((ns (hc-sym-ns h)))
+                (or (jolt-nil? ns) (and (string? ns) (string=? ns "clojure.core"))))))))
 (define (hc-second x) (seq-first (jolt-seq (seq-more x))))
 
 (define (hc-sq-symbol ctx form gsmap)

host/chez/java/records-interop.ss

@@ -93,8 +93,13 @@
       ((jrec? val)
        (let ((tag (jrec-tag val)))
          (or (string=? tag tname)
-             (and (> (string-length tag) (string-length tname))
+             ;; a simple name matches a qualified tag only at a `.` boundary:
-                  (string=? (substring tag (- (string-length tag) (string-length tname)) (string-length tag)) tname))
+             ;; "a.b.IntervalFD" is an IntervalFD, but "a.b.MultiIntervalFD" is NOT
+             ;; (a raw string-suffix would wrongly match the latter).
+             (let ((tl (string-length tag)) (nl (string-length tname)))
+               (and (fx>? tl nl)
+                    (char=? (string-ref tag (fx- (fx- tl nl) 1)) #\.)
+                    (string=? (substring tag (fx- tl nl) tl) tname)))
              ;; a protocol/interface the type implements (defprotocol generates an
              ;; interface; (instance? SomeProtocol record) is true when the record
              ;; implements it — core.match dispatches on instance? IPatternCompile).

host/chez/reader.ss

@@ -589,10 +589,13 @@
                            (jolt-list (jolt-symbol #f "syntax-quote") form))
                        j)))
             ((char=? c #\@) (rdr-wrap s (+ i 1) end (jolt-symbol "clojure.core" "deref")))
+            ;; ~ / ~@ read as clojure.core/unquote(-splicing), like the JVM reader —
+            ;; so code that inspects pattern/template data (core.logic's defne) sees
+            ;; the qualified symbol it expects.
             ((char=? c #\~)
              (if (and (< (+ i 1) end) (char=? (string-ref s (+ i 1)) #\@))
-                 (rdr-wrap s (+ i 2) end (jolt-symbol #f "unquote-splicing"))
+                 (rdr-wrap s (+ i 2) end (jolt-symbol "clojure.core" "unquote-splicing"))
-                 (rdr-wrap s (+ i 1) end (jolt-symbol #f "unquote"))))
+                 (rdr-wrap s (+ i 1) end (jolt-symbol "clojure.core" "unquote"))))
             ((char=? c #\^)
              (let-values (((mform j) (rdr-read-form s (+ i 1) end)))
                (let-values (((target k) (rdr-read-form s j end)))

test/chez/corpus.edn

@@ -3347,4 +3347,6 @@
   {:suite "special forms / qualified" :label "clojure.core-qualified special form (from syntax-quote)" :expected "[:g 9]" :actual "(clojure.core/letfn [(g [x] [:g x])] (g 9))"}
   {:suite "symbols / interning" :label "(str sym) is the symbol's interned name (identity-stable)" :expected "[true true]" :actual "(let [s (quote ?a)] [(identical? (name s) (str s)) (= (str s) \"?a\")])"}
   {:suite "symbols / interning" :label "equal symbols share an interned name string" :expected "true" :actual "(let [a (quote ?foo) b (quote ?foo)] (identical? (name a) (name b)))"}
+  {:suite "reader / unquote" :label "~x reads as clojure.core/unquote" :expected "true" :actual "(= (quote (clojure.core/unquote v)) (read-string \"~v\"))"}
+  {:suite "reader / unquote" :label "~@x reads as clojure.core/unquote-splicing" :expected "clojure.core/unquote-splicing" :actual "(first (read-string \"~@xs\"))"}
 ]

test/chez/unit.edn

@@ -323,8 +323,8 @@
   {:suite "reader" :expr "(= [1 [2 3] {:k :v}] (read-string \"[1 [2 3] {:k :v}]\"))" :expected "true"}
   {:suite "reader" :expr "(= (quote (quote x)) (read-string \"'x\"))" :expected "true"}
   {:suite "reader" :expr "(= (quote (clojure.core/deref a)) (read-string \"@a\"))" :expected "true"}
-  {:suite "reader" :expr "(= (quote (syntax-quote (a (unquote b)))) (read-string \"`(a ~b)\"))" :expected "true"}
+  {:suite "reader" :expr "(= (quote (syntax-quote (a (clojure.core/unquote b)))) (read-string \"`(a ~b)\"))" :expected "true"}
-  {:suite "reader" :expr "(= (quote (unquote-splicing xs)) (read-string \"~@xs\"))" :expected "true"}
+  {:suite "reader" :expr "(= (quote (clojure.core/unquote-splicing xs)) (read-string \"~@xs\"))" :expected "true"}
   {:suite "reader" :expr "(= 42 (read-string \"; comment\\n42\"))" :expected "true"}
   {:suite "reader" :expr "(= [1 2] (read-string \"[1 #_ 9 2]\"))" :expected "true"}
   {:suite "reader" :expr "(nil? (read-string \"\"))" :expected "true"}