Extra work

- [ ] `read_persistent`, `load_persistent`, `revert_to_persistent`
_Originally posted by @Dampfwalze in https://github.com/MolotovCherry/virtual-display-rs/issues/116#issuecomment-2054036704_
- [x]  Sending Result and making proper error types specific to the functions
_https://github.com/MolotovCherry/virtual-display-rs/pull/116#discussion_r1564658911_
            