* chore: Add mathjs dependency
* refactor: Replace eval with mathjs for safer expression evaluation and improve session expiry handling to not environment variables from data-schemas package
* test: Add integration tests for math function with environment variable expressions
* refactor: Update test description for clarity on expiresIn behavior
* refactor: Update test cases to clarify default expiration behavior for token generation
* refactor: Improve error handling in math function for clearer evaluation errors
