Fix stack overflow when converting arrays with circular references to primitives

[monkeyWie]

Summary

Stack overflow occurs in goja when attempting to convert an object containing a circular reference to a primitive value (via toPrimitive, toString, toNumeric, etc.).

Minimal Reproduction

package main

import (
	"fmt"
	"github.com/dop251/goja"
)

func main() {
	vm := goja.New()
	
	code := `
		var T = [1, 2, 3];
		T[42] = T;       // Create circular reference
		var x = T % 2;   // Modulo operation triggers toPrimitive -> toString
	`
	
	_, err := vm.RunString(code)
	if err != nil {
		fmt.Printf("ERROR: %v\n", err)
	}
}

Environment

• Go version: go1.25.4 darwin/arm64
• OS: macOS

[dop251]

Thanks for submitting thiis! I've added a few comments.

[monkeyWie]

@dop251 has already submitted a modification, please review