Fix composer description

Updated composer.json description (PSR-15 to PSR-7)

Initial Version

Version 1.0.0 – Initial Release

Key Features:

• URI Signing: Securely sign URIs to guarantee their integrity.
• Signature Validation: Validate signed URIs to confirm their authenticity.
• Customizable Expiration: Set expiration times for signed URIs, ensuring they are only valid for a specific duration.
• HMAC-Based Security: Uses industry-standard HMAC algorithms to sign and verify URIs.