Step 5 piece 6: migrate 23 .sx files to define-library/import

Wraps all core .sx files in R7RS define-library with explicit export
lists, plus (import ...) at end for backward-compatible global re-export.

Libraries registered:
  (sx bytecode)      — 83 opcode constants
  (sx render)        — 15 tag registries + render helpers
  (sx signals)       — 23 reactive signal primitives
  (sx r7rs)          — 21 R7RS aliases
  (sx compiler)      — 42 compiler functions
  (sx vm)            — 32 VM functions
  (sx freeze)        — 9 freeze/thaw functions
  (sx content)       — 6 content store functions
  (sx callcc)        — 1 call/cc wrapper
  (sx highlight)     — 13 syntax highlighting functions
  (sx stdlib)        — 47 stdlib functions
  (sx swap)          — 13 swap algebra functions
  (sx render-trace)  — 8 render trace functions
  (sx harness)       — 21 test harness functions
  (sx canonical)     — 12 canonical serialization functions
  (web adapter-html) — 13 HTML renderer functions
  (web adapter-sx)   — 13 SX wire format functions
  (web engine)       — 33 hypermedia engine functions
  (web request-handler) — 4 request handling functions
  (web page-helpers) — 12 page helper functions
  (web router)       — 36 routing functions
  (web deps)         — 19 dependency analysis functions
  (web orchestration) — 59 page orchestration functions

Key changes:
- define-library now inherits parent env (env-extend env instead of
  env-extend make-env) so library bodies can access platform primitives
- sx_server.ml: added resolve_library_path + load_library_file for
  import resolution (maps library specs to file paths)
- cek_run_with_io: handles "import" locally instead of sending to
  Python bridge

2608/2608 tests passing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

spec/canonical.sx

@@ -1,4 +1,21 @@
 ;; Deterministic serialization for content addressing
+
+(define-library (sx canonical)
+  (export
+    canonical-serialize
+    canonical-number
+    canonical-dict
+    content-id
+    content-id-short
+    make-bytecode-module
+    bytecode-module?
+    bytecode-module-version
+    bytecode-module-source-hash
+    bytecode-module-code
+    make-code-object
+    make-provenance)
+  (begin
+
 (define
   canonical-serialize
   :effects ()
@@ -127,3 +144,9 @@
       :bytecode-cid bytecode-cid
       :compiler-cid compiler-cid
       :timestamp timestamp)))
+
+
+)) ;; end define-library
+
+;; Re-export to global namespace for backward compatibility
+(import (sx canonical))

spec/evaluator.sx

@@ -1469,9 +1469,7 @@
     (let
       ((lib-spec (first args)) (decls (rest args)))
       (let
-        ((lib-env (env-extend (make-env)))
-          (exports (list))
-          (body-forms (list)))
+        ((lib-env (env-extend env)) (exports (list)) (body-forms (list)))
         (for-each
           (fn
             (decl)

spec/harness.sx

@@ -1,4 +1,30 @@
 ;; Assert condition is truthy, error with message
+
+(define-library (sx harness)
+  (export
+    assert
+    assert=
+    default-platform
+    make-harness
+    harness-reset!
+    harness-log
+    harness-get
+    harness-set!
+    make-interceptor
+    install-interceptors
+    io-calls
+    io-call-count
+    io-call-nth
+    io-call-args
+    io-call-result
+    assert-io-called
+    assert-no-io
+    assert-io-count
+    assert-io-args
+    assert-io-result
+    assert-state)
+  (begin
+
 (define assert (fn (condition msg) (when (not condition) (error (or msg "Assertion failed")))))
 
 ;; Assert two values are equal
@@ -60,3 +86,9 @@
 
 ;; Assert a state key has the expected value
 (define assert-state :effects () (fn (session key expected) (let ((actual (harness-get session key))) (assert (equal? actual expected) (str "Expected state " key " to be " (str expected) " but got " (str actual))))))
+
+
+)) ;; end define-library
+
+;; Re-export to global namespace for backward compatibility
+(import (sx harness))

spec/render.sx

@@ -1,4 +1,24 @@
 ;; Registry of all valid HTML tag names
+
+(define-library (sx render)
+  (export
+    HTML_TAGS
+    VOID_ELEMENTS
+    BOOLEAN_ATTRS
+    *definition-form-extensions*
+    definition-form?
+    parse-element-args
+    render-attrs
+    eval-cond
+    eval-cond-scheme
+    eval-cond-clojure
+    process-bindings
+    is-render-expr?
+    merge-spread-attrs
+    escape-html
+    escape-attr)
+  (begin
+
 (define
   HTML_TAGS
   (list
@@ -413,3 +433,9 @@
 
 ;; Escape special chars for HTML attribute values
 (define escape-attr (fn (s) (escape-html s)))
+
+
+)) ;; end define-library
+
+;; Re-export to global namespace for backward compatibility
+(import (sx render))

spec/signals.sx

@@ -1,3 +1,32 @@
+
+
+(define-library (sx signals)
+  (export
+    make-signal
+    signal?
+    signal-value
+    signal-set-value!
+    signal-subscribers
+    signal-add-sub!
+    signal-remove-sub!
+    signal-deps
+    signal-set-deps!
+    signal
+    deref
+    reset!
+    swap!
+    computed
+    effect
+    *batch-depth*
+    *batch-queue*
+    batch
+    notify-subscribers
+    flush-subscribers
+    dispose-computed
+    with-island-scope
+    register-in-scope)
+  (begin
+
 (define
   make-signal
   (fn
@@ -193,3 +222,9 @@
     (let
       ((collector (scope-peek "sx-island-scope")))
       (when collector (cek-call collector (list disposable))))))
+
+
+)) ;; end define-library
+
+;; Re-export to global namespace for backward compatibility
+(import (sx signals))