HS Bucket F: array literal arg to JS fn fix (+1 test)

Generator emit_eval translates arr.reduce/map/filter to SX primitives
so SX list args work. host-call-fn sxToJs converts SX lists to native
JS arrays for native JS function calls. Fixes functionCalls
"can pass an array literal as an argument".

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

tests/playwright/generate-sx-tests.py

@@ -1666,6 +1666,13 @@ def js_expr_to_sx(expr):
             if s is None:
                 return None
             arg_sx.append(s)
+        # Translate common array HO methods to SX primitives so SX lists work.
+        if method == 'reduce' and len(arg_sx) == 2:
+            return f'(reduce {arg_sx[0]} {arg_sx[1]} {obj})'
+        if method == 'map' and len(arg_sx) == 1:
+            return f'(map {arg_sx[0]} {obj})'
+        if method == 'filter' and len(arg_sx) == 1:
+            return f'(filter {arg_sx[0]} {obj})'
         return f'(host-call {obj} "{method}" {" ".join(arg_sx)})'.strip()
 
     # Property access: o.prop