Remove token revocation logic and unused dependencies

Eliminated the `RevokedToken` model and associated logic for managing token revocation. Removed unused files, related tests, and outdated dependencies in authentication modules. Simplified token decoding, user validation, and dependency injection by streamlining the flow and enhancing maintainability.

backend/app/models/user.py

@@ -25,7 +25,6 @@ class User(Base, UUIDMixin, TimestampMixin):
         foreign_keys="EventManager.user_id"
     )
     guest_profiles = relationship("Guest", back_populates="user", foreign_keys="Guest.user_id")
-    revoked_tokens = relationship("RevokedToken", back_populates="user", cascade="all, delete")
 
     def __repr__(self):
         return f"<User {self.email}>"