Add interactive JWT demo showcasing JWT.NET library integration with Ivy

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This PR adds a comprehensive JWT (JSON Web Token) demo application that showcases the integration of the JWT.NET library with the Ivy interactive web framework.

Features

The demo provides a complete JWT workflow with an intuitive web interface:

🔑 Token Generation

• Interactive form to create JWT tokens with custom claims
• Supports username, email, and role selection (User/Admin/Moderator)
• Includes standard JWT claims: iat (issued at), exp (expires), iss (issuer), aud (audience)
• Uses HMAC SHA-256 algorithm for secure token signing

🔍 Token Operations

• Token Validation: Verifies JWT signatures and decodes payload with full verification
• Token Decoding: Inspects token contents without signature verification (useful for debugging)
• Claims Extraction: Formats and displays specific claims with human-readable timestamps

📋 Interactive Results

• JSON syntax highlighting with line numbers
• Copy-to-clipboard functionality for easy token sharing
• Real-time error handling with descriptive messages

Technical Implementation

• Built using the JWT.NET library (v10.1.1) with the recommended JWT Builder pattern
• Targets .NET 9.0 for compatibility with the latest Ivy framework
• Uses proper JWT validation with JwtBuilder.Create() for secure token operations
• Implements clean separation between token generation, validation, and decoding operations

Educational Value

The demo includes comprehensive documentation explaining:

• JWT concepts and use cases
• Security best practices for production applications
• Links to jwt.io and the JWT.NET library documentation
• Clear examples of each JWT operation

Security Notes

The demo uses a hardcoded secret key for demonstration purposes and includes prominent warnings about using proper secrets management in production applications.

Fixes #25.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

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• aka.ms
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If you need me to access, download, or install something from one of these locations, you can either:

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