Fix Proxy construct trap receiving Array-constructor-mangled arguments

Jint.Tests/Runtime/ProxyTests.cs

@@ -41,6 +41,24 @@ public void AccessingPropertyOnRevokedProxyThrowsTypeError()
         AssertJsTypeError(_engine, ex, "Cannot perform 'foo' on a proxy that has been revoked");
     }
 
+    [Fact]
+    public void ConstructTrapReceivesCreateArrayFromListArguments()
+    {
+        var result = _engine.Evaluate("""
+            var p = new Proxy(function () {}, { construct: (t, args) => ({ len: args.length, first: args[0] }) });
+            var r = new p(42);
+            r.len + ':' + r.first;
+            """).AsString();
+        Assert.Equal("1:42", result);
+    }
+
+    [Fact]
+    public void ConstructTrapAcceptsSingleFractionalArgument()
+    {
+        var result = _engine.Evaluate("new (new Proxy(function () {}, { construct: (t, args) => ({ v: args[0] }) }))(1.5).v");
+        Assert.Equal(1.5, result.AsNumber());
+    }
+
     [Fact]
     public void ProxyToStringUseTarget()
     {

Jint/Native/JsProxy.cs

@@ -85,7 +85,9 @@ ObjectInstance IConstructor.Construct(JsCallArguments arguments, JsValue newTarg
             Throw.TypeError(_engine.Realm, "Proxy target is not a constructor");
         }
 
-        var argArray = _engine.Realm.Intrinsics.Array.Construct(arguments, _engine.Realm.Intrinsics.Array);
+        // step 7: CreateArrayFromList(argumentsList) - must not use Array constructor semantics,
+        // a single numeric argument would create a hole-filled array of that length
+        var argArray = _engine.Realm.Intrinsics.Array.ConstructFast(arguments);
 
         if (!TryCallHandler(TrapConstruct, [_target, argArray, newTarget], out var result))
         {