HS: open/close commands for dialog/details — 428→435

- Parser: open/close commands with optional target (defaults to me)
- Compiler: open-element → hs-open!, close-element → hs-close!
- Runtime: hs-open! calls showModal() for dialogs, sets open=true for details
- Runtime: hs-close! calls close() for dialogs, sets open=false for details
- dialog: 1/10 → 8/10

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

lib/hyperscript/runtime.sx

@@ -475,8 +475,30 @@
             ((= tag "FORM") (dom-set-inner-html target ""))
             (true (dom-set-inner-html target ""))))))))
 ;; Collection: split by
-(define hs-first (fn (lst) (first lst)))
+(define
+  hs-open!
+  (fn
+    (el)
+    (let
+      ((tag (dom-get-prop el "tagName")))
+      (if
+        (= tag "DIALOG")
+        (host-call el "showModal")
+        (dom-set-prop el "open" true)))))
 ;; Collection: joined by
+(define
+  hs-close!
+  (fn
+    (el)
+    (let
+      ((tag (dom-get-prop el "tagName")))
+      (if
+        (= tag "DIALOG")
+        (host-call el "close")
+        (dom-set-prop el "open" false)))))
+
+(define hs-first (fn (lst) (first lst)))
+
 (define hs-last (fn (lst) (last lst)))
 
 (define