feat: add token validation service method
refactor: update middleware to use structured DTOs
feat: implement session info propagation through context
refactor: replace ad-hoc structs with DTOs in middleware
chore: organize auth-related data structures
feat: implement Redis caching for terminated sessions
feat: add new session GUID queries for validation
refactor: extend Session model with last_refresh_exp_time
refactor: update token generation to include role and session
refactor: modify auth middleware to validate session status
refactor: replace GetUserSessions with GetValidUserSessions
chore: add uuid/v5 dependency
fix: update router to pass dependencies to auth middleware
chore: update SQL schema and queries for new expiration field
feat: very minimal implementation of registration functions;
refactor: login function now uses the transactional db helper function and creates a session;
feat: enum for jwt token type
