Step 17b: bytecode-compiled text-layout, WASM library import fix

- text-layout.sx added to WASM bytecode pipeline (9K compiled)
- Fix multi-list map calls (map-indexed + nth instead of map fn list1 list2)
- pretext-layout-lines and pretext-position-line moved to library exports
- Browser load-sxbc: handle VmSuspended for import, copy library exports
  to global_env after module load (define-library export fix)
- compile-modules.js: text-layout in SOURCE_MAP, FILES, and entry deps
- Island uses library functions (break-lines, pretext-layout-lines)
  instead of inlining — runs on bytecode VM when exports resolve

Known issue: define-library exports don't propagate to browser global env
yet. The load-sxbc import suspension handler resumes correctly but
bind_import_set doesn't fire. Needs deeper investigation into how the
WASM kernel's define-library registers exports vs how other libraries
(adapter-html, tw) make their exports available.

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

lib/hyperscript/compiler.sx

@@ -314,7 +314,10 @@
           (true
             (let
               ((t (hs-to-sx expr)))
-              (list (quote set!) t (list (quote +) t amount)))))))
+              (list
+                (quote set!)
+                t
+                (list (quote +) (list (quote or) t 0) amount)))))))
     (define
       emit-dec
       (fn
@@ -363,7 +366,10 @@
           (true
             (let
               ((t (hs-to-sx expr)))
-              (list (quote set!) t (list (quote -) t amount)))))))
+              (list
+                (quote set!)
+                t
+                (list (quote -) (list (quote or) t 0) amount)))))))
     (define
       emit-behavior
       (fn
@@ -801,8 +807,23 @@
                       (list (quote hs-query-all) (nth raw-tgt 1)))
                     (list
                       (quote dom-remove-class)
-                      (hs-to-sx raw-tgt)
+                      (if (nil? raw-tgt) (quote me) (hs-to-sx raw-tgt))
                       (nth ast 1)))))
+              ((= head (quote remove-element))
+                (list (quote dom-remove) (hs-to-sx (nth ast 1))))
+              ((= head (quote remove-attr))
+                (let
+                  ((tgt (if (nil? (nth ast 2)) (quote me) (hs-to-sx (nth ast 2)))))
+                  (list (quote dom-remove-attr) tgt (nth ast 1))))
+              ((= head (quote remove-css))
+                (let
+                  ((tgt (if (nil? (nth ast 2)) (quote me) (hs-to-sx (nth ast 2))))
+                    (props (nth ast 1)))
+                  (cons
+                    (quote do)
+                    (map
+                      (fn (p) (list (quote dom-set-style) tgt p ""))
+                      props))))
               ((= head (quote toggle-class))
                 (list
                   (quote hs-toggle-class!)

lib/hyperscript/parser.sx

@@ -727,30 +727,68 @@
         parse-remove-cmd
         (fn
           ()
-          (if
-            (= (tp-type) "class")
-            (let
-              ((cls (get (adv!) "value")) (extra-classes (list)))
-              (define
-                collect-classes!
-                (fn
-                  ()
-                  (when
-                    (= (tp-type) "class")
-                    (set!
-                      extra-classes
-                      (append extra-classes (list (get (adv!) "value"))))
-                    (collect-classes!))))
-              (collect-classes!)
+          (cond
+            ((= (tp-type) "class")
               (let
-                ((tgt (parse-tgt-kw "from" (list (quote me)))))
+                ((cls (get (adv!) "value")) (extra-classes (list)))
+                (define
+                  collect-classes!
+                  (fn
+                    ()
+                    (when
+                      (= (tp-type) "class")
+                      (set!
+                        extra-classes
+                        (append extra-classes (list (get (adv!) "value"))))
+                      (collect-classes!))))
+                (collect-classes!)
+                (let
+                  ((tgt (if (match-kw "from") (parse-expr) nil)))
+                  (if
+                    (empty? extra-classes)
+                    (list (quote remove-class) cls tgt)
+                    (cons
+                      (quote multi-remove-class)
+                      (cons tgt (cons cls extra-classes)))))))
+            ((and (= (tp-type) "bracket-open") (= (tp-val) "["))
+              (do
+                (adv!)
                 (if
-                  (empty? extra-classes)
-                  (list (quote remove-class) cls tgt)
-                  (cons
-                    (quote multi-remove-class)
-                    (cons tgt (cons cls extra-classes))))))
-            nil)))
+                  (= (tp-type) "attr")
+                  (let
+                    ((attr-name (get (adv!) "value")))
+                    (match-kw "]")
+                    (let
+                      ((tgt (if (match-kw "from") (parse-expr) nil)))
+                      (list (quote remove-attr) attr-name tgt)))
+                  nil)))
+            ((= (tp-val) "{")
+              (do
+                (adv!)
+                (let
+                  ((props (list)))
+                  (define
+                    collect-props!
+                    (fn
+                      ()
+                      (when
+                        (not (= (tp-val) "}"))
+                        (when (= (tp-val) ";") (adv!))
+                        (when
+                          (not (= (tp-val) "}"))
+                          (set!
+                            props
+                            (append props (list (get (adv!) "value"))))
+                          (collect-props!)))))
+                  (collect-props!)
+                  (match-kw "}")
+                  (let
+                    ((tgt (if (match-kw "from") (parse-expr) nil)))
+                    (list (quote remove-css) props tgt)))))
+            (true
+              (let
+                ((target (parse-expr)))
+                (list (quote remove-element) target))))))
       (define
         parse-toggle-cmd
         (fn
@@ -1168,6 +1206,7 @@
           ()
           (let
             ((target (parse-expr)))
+            (match-kw "then")
             (let
               ((body (parse-cmd-list)))
               (match-kw "end")

lib/text-layout.sx

@@ -13,6 +13,21 @@
 ;; Knuth-Plass optimal line breaking (DP over break candidates).
 ;; Liang's hyphenation (trie over character patterns).
 
+(define
+  pretext-position-line
+  (fn
+    (words widths gap-w)
+    (let
+      loop
+      ((i 0) (x 0) (acc (list)))
+      (if
+        (>= i (len words))
+        acc
+        (loop
+          (+ i 1)
+          (+ x (nth widths i) gap-w)
+          (append acc (list {:width (nth widths i) :x x :word (nth words i)})))))))
+
 (define-library
   (sx text-layout)
   (export
@@ -25,6 +40,8 @@
     break-lines-greedy
     position-line
     position-lines
+    pretext-position-line
+    pretext-layout-lines
     layout-paragraph
     make-hyphenation-trie
     find-hyphenation-points
@@ -131,7 +148,7 @@
               ((starts (cons 0 breaks)))
               (let
                 ((ends (append (rest starts) (list n))))
-                (map (fn (s e) (list s e)) starts ends)))))))
+                (map-indexed (fn (i s) (list s (nth ends i))) starts)))))))
     (define
       position-line
       (fn
@@ -266,7 +283,7 @@
             (let
               ((starts (cons 0 points))
                 (ends (append points (list (len word)))))
-              (map (fn (s e) (slice word s e)) starts ends))))))
+              (map-indexed (fn (i s) (slice word s (nth ends i))) starts))))))
     (define
       layout-paragraph
       (fn