Integrate OnchainKit into Next.js application

[homanp]

This pull request integrates OnchainKit into our Next.js application. Here's a summary of the changes:

1. Added OnchainKit styles to globals.css
2. Created a new Providers component to wrap the application with OnchainKitProvider
3. Updated RootLayout to use the new Providers component
4. Modified the home page (page.tsx) to include information about OnchainKit integration and updated links

These changes set up the basic structure for using OnchainKit in our project. Developers will need to add their Coinbase Developer Platform API key to the .env file to fully enable OnchainKit functionality.

To complete the setup:

1. Obtain a Client API Key from the Coinbase Developer Platform
2. Create a .env file in the project root and add: NEXT_PUBLIC_ONCHAINKIT_API_KEY=YOUR_CLIENT_API_KEY
3. Create app/providers.tsx with the OnchainKitProvider configuration

Next steps:

• Start using OnchainKit components and utilities in your application
• Refer to the OnchainKit documentation for more advanced usage and features