HS: as HTML (NodeList elements via outerHTML) + as Fragment (+4 tests)

hs-coerce HTML list case: use outerHTML for element items, not str.
hs-coerce Fragment case: actually build a DocumentFragment — element
items are appended directly; strings are parsed via a temp div.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/hyperscript/runtime.sx

@@ -1210,7 +1210,14 @@
       ((= type-name "Array") (if (list? value) value (list value)))
       ((= type-name "HTML")
         (cond
-          ((list? value) (join "" (map (fn (x) (str x)) value)))
+          ((list? value)
+            (join
+              ""
+              (map
+                (fn
+                  (x)
+                  (if (hs-element? x) (host-get x "outerHTML") (str x)))
+                value)))
           ((hs-element? value) (host-get value "outerHTML"))
           (true (str value))))
       ((= type-name "JSON")
@@ -1261,7 +1268,25 @@
               ((factor (pow 10 digits)))
               (str (/ (floor (+ (* num factor) 0.5)) factor))))))
       ((= type-name "Selector") (str value))
-      ((= type-name "Fragment") value)
+      ((= type-name "Fragment")
+        (let
+          ((frag (host-call (dom-document) "createDocumentFragment")))
+          (do
+            (for-each
+              (fn
+                (item)
+                (if
+                  (hs-element? item)
+                  (dom-append frag item)
+                  (let
+                    ((tmp (dom-create-element "div")))
+                    (do
+                      (dom-set-inner-html tmp (str item))
+                      (for-each
+                        (fn (k) (dom-append frag k))
+                        (host-get tmp "children"))))))
+              (if (list? value) value (list value)))
+            frag)))
       ((= type-name "Values") (hs-as-values value))
       ((= type-name "Keys")
         (if