Add `Color.from_hex`

See https://github.com/pygame-community/pygame-ce/pull/3379, specifically:
- https://github.com/pygame-community/pygame-ce/pull/3379#issuecomment-2781994179
- https://github.com/pygame-community/pygame-ce/pull/3379#pullrequestreview-2795797360

Just follow the same principles used for all the other `Color.from_*` methods