HS: split type-check (predicate) from type-assert (:) — +5 comparisonOperator

Last commit's `hs-type-check` rewrite collapsed predicate and assertion
into one runtime fn that always raised on mismatch. That fixed `: Type`
but broke `is a Type` / `is not a Type` (which need a bool):

  null is a String       expected true,  got nil   (raised)
  null is not a String   expected false, got true  (default boolean)

Restored the split. Parser now emits `(type-assert ...)` for `:` and
keeps `(type-check ...)` for `is a` / `is not a`. Runtime adds:
- `hs-type-check`        — predicate, never raises (nil passes)
- `hs-type-check-strict` — predicate, false on nil
- `hs-type-assert`       — value or raises
- `hs-type-assert-strict` — value or raises (also raises on nil)
Compiler maps `type-assert` / `type-assert-strict` to the new runtime fns.

comparisonOperator 74/83 → 79/83 (+5: `is a/an`, `is not a/an` four tests
plus a fifth that depended on them). typecheck stays 2/5 (no regression).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lib/hyperscript/compiler.sx

@@ -1703,6 +1703,16 @@
                   (quote hs-type-check-strict)
                   (hs-to-sx (nth ast 1))
                   (nth ast 2)))
+              ((= head (quote type-assert))
+                (list
+                  (quote hs-type-assert)
+                  (hs-to-sx (nth ast 1))
+                  (nth ast 2)))
+              ((= head (quote type-assert-strict))
+                (list
+                  (quote hs-type-assert-strict)
+                  (hs-to-sx (nth ast 1))
+                  (nth ast 2)))
               ((= head (quote strict-eq))
                 (list
                   (quote hs-strict-eq)

lib/hyperscript/parser.sx

@@ -678,8 +678,8 @@
                         (when strict (adv!))
                         (if
                           strict
-                          (list (quote type-check-strict) left type-name)
-                          (list (quote type-check) left type-name)))))))
+                          (list (quote type-assert-strict) left type-name)
+                          (list (quote type-assert) left type-name)))))))
               ((and (= typ "keyword") (= val "of"))
                 (do
                   (adv!)

lib/hyperscript/runtime.sx

@@ -769,28 +769,48 @@
     (dom-set-style target prop (str to-val))
     (when duration (hs-settle target))))
 
-(define
-  hs-type-check
-  (fn
-    (value type-name)
-    (if
-      (nil? value)
-      value
-      (let
-        ((matches (cond ((= type-name "Number") (number? value)) ((= type-name "String") (string? value)) ((= type-name "Boolean") (or (= value true) (= value false))) ((= type-name "Array") (list? value)) ((= type-name "Object") (dict? value)) ((= type-name "Element") (= (host-typeof value) "element")) ((= type-name "Node") (or (= (host-typeof value) "element") (= (host-typeof value) "text"))) (true (= (host-typeof value) (downcase type-name))))))
-        (if
-          matches
-          value
-          (raise (str "Typecheck failed! expected " type-name)))))))
+(begin
+  (define
+    hs-type-check
+    (fn
+      (value type-name)
+      (if
+        (nil? value)
+        true
+        (cond
+          ((= type-name "Number") (number? value))
+          ((= type-name "String") (string? value))
+          ((= type-name "Boolean") (or (= value true) (= value false)))
+          ((= type-name "Array") (list? value))
+          ((= type-name "Object") (dict? value))
+          ((= type-name "Element") (= (host-typeof value) "element"))
+          ((= type-name "Node")
+            (or
+              (= (host-typeof value) "element")
+              (= (host-typeof value) "text")))
+          (true (= (host-typeof value) (downcase type-name)))))))
+  (define
+    hs-type-assert
+    (fn
+      (value type-name)
+      (if
+        (hs-type-check value type-name)
+        value
+        (raise (str "Typecheck failed! expected " type-name)))))
+  (define
+    hs-type-assert-strict
+    (fn
+      (value type-name)
+      (if
+        (nil? value)
+        (raise (str "Typecheck failed! expected " type-name " but got nil"))
+        (hs-type-assert value type-name)))))
 
 (define
   hs-type-check-strict
   (fn
     (value type-name)
-    (if
-      (nil? value)
-      (raise (str "Typecheck failed! expected " type-name " but got nil"))
-      (hs-type-check value type-name))))
+    (if (nil? value) false (hs-type-check value type-name))))
 
 (define
   hs-strict-eq

shared/static/wasm/sx/hs-compiler.sx

@@ -1703,6 +1703,16 @@
                   (quote hs-type-check-strict)
                   (hs-to-sx (nth ast 1))
                   (nth ast 2)))
+              ((= head (quote type-assert))
+                (list
+                  (quote hs-type-assert)
+                  (hs-to-sx (nth ast 1))
+                  (nth ast 2)))
+              ((= head (quote type-assert-strict))
+                (list
+                  (quote hs-type-assert-strict)
+                  (hs-to-sx (nth ast 1))
+                  (nth ast 2)))
               ((= head (quote strict-eq))
                 (list
                   (quote hs-strict-eq)

shared/static/wasm/sx/hs-parser.sx

@@ -678,8 +678,8 @@
                         (when strict (adv!))
                         (if
                           strict
-                          (list (quote type-check-strict) left type-name)
-                          (list (quote type-check) left type-name)))))))
+                          (list (quote type-assert-strict) left type-name)
+                          (list (quote type-assert) left type-name)))))))
               ((and (= typ "keyword") (= val "of"))
                 (do
                   (adv!)

shared/static/wasm/sx/hs-runtime.sx

@@ -769,28 +769,48 @@
     (dom-set-style target prop (str to-val))
     (when duration (hs-settle target))))
 
-(define
-  hs-type-check
-  (fn
-    (value type-name)
-    (if
-      (nil? value)
-      value
-      (let
-        ((matches (cond ((= type-name "Number") (number? value)) ((= type-name "String") (string? value)) ((= type-name "Boolean") (or (= value true) (= value false))) ((= type-name "Array") (list? value)) ((= type-name "Object") (dict? value)) ((= type-name "Element") (= (host-typeof value) "element")) ((= type-name "Node") (or (= (host-typeof value) "element") (= (host-typeof value) "text"))) (true (= (host-typeof value) (downcase type-name))))))
-        (if
-          matches
-          value
-          (raise (str "Typecheck failed! expected " type-name)))))))
+(begin
+  (define
+    hs-type-check
+    (fn
+      (value type-name)
+      (if
+        (nil? value)
+        true
+        (cond
+          ((= type-name "Number") (number? value))
+          ((= type-name "String") (string? value))
+          ((= type-name "Boolean") (or (= value true) (= value false)))
+          ((= type-name "Array") (list? value))
+          ((= type-name "Object") (dict? value))
+          ((= type-name "Element") (= (host-typeof value) "element"))
+          ((= type-name "Node")
+            (or
+              (= (host-typeof value) "element")
+              (= (host-typeof value) "text")))
+          (true (= (host-typeof value) (downcase type-name)))))))
+  (define
+    hs-type-assert
+    (fn
+      (value type-name)
+      (if
+        (hs-type-check value type-name)
+        value
+        (raise (str "Typecheck failed! expected " type-name)))))
+  (define
+    hs-type-assert-strict
+    (fn
+      (value type-name)
+      (if
+        (nil? value)
+        (raise (str "Typecheck failed! expected " type-name " but got nil"))
+        (hs-type-assert value type-name)))))
 
 (define
   hs-type-check-strict
   (fn
     (value type-name)
-    (if
-      (nil? value)
-      (raise (str "Typecheck failed! expected " type-name " but got nil"))
-      (hs-type-check value type-name))))
+    (if (nil? value) false (hs-type-check value type-name))))
 
 (define
   hs-strict-eq