Composer: Add firebase/php-jwt as dependency

[sergiosant02]

This PR adds firebase/php-jwt as composer dependency.

General Information:

• This dependency was already used in ILIAS.
• License: BSD-3

Usage:

• Used in LTIConsumer & LTIProvider components.

Wrapped By:

• components/ILIAS/LTIConsumer
• components/ILIAS/LTIProvider

Reasoning:

• The php-jwt dependency is used in LTIProvider and LTIConsumer to handle JWT (JSON Web Tokens) for secure communication and authentication between platforms, ensuring token creation, validation, and decoding in compliance with LTI standards.

Maintenance:

The php-jwt dependency, maintained by Google's Firebase team, provides robust support for JWT handling with regular updates, ensuring reliability and alignment with current security standards.

Last update: 09 April 2025

Links: https://github.com/firebase/php-jwt

[matthiaskunkel]

Jour Fixe, 08 DEC 2025: Dependency is accepted for ILIAS 12.