Jixxeo Calculator

Emergent Prompt: Jixxeo Calculator Create Jixxeo Calculator as a fully functional app inside my existing Jixxeo Apps website. - Add a modern calculator with basic math, percentages, and an advanced scientific calculator. - Include calculation history and the ability to clear or reuse previous calculations. - Add free and premium subscription plans. Premium members unlock advanced calculator features, extra themes, and additional tools. - Add a Tip Jixxeo button so members can voluntarily support the app through secure payments. - Include an admin dashboard to manage subscriptions, premium features, tips, and settings. - Integrate with the existing Jixxeo Apps member accounts so signed-in members do not need to create another account. - Match the existing Jixxeo Apps design and make the calculator mobile-friendly. - Keep the app completely ad-free. - Make everything functional, with secure payments and subscription cancellation.