Unreadable file causes CRATE to not backup/error silently

[jamess60]

Bad file paths cause crate to fail the source read check and exit without ntfy notification

1. Implement option to exclude bad file paths
2. Implement ntfy notification to prevent this fail condition

`root@V-CONT-02:~# systemctl status crate.service
○ crate.service - CRATE (Container Recovery and Archival ToolsEt)
Loaded: loaded (/etc/systemd/system/crate.service; static)
Active: inactive (dead) since Thu 2025-04-24 01:00:12 BST; 10h ago
Duration: 3.182s
TriggeredBy: ● crate.timer
Process: 1255 ExecStart=/usr/bin/python3 /usr/share/crate/src/crate.py -m bl (code=exited, status=0/SUCCESS)
Main PID: 1255 (code=exited, status=0/SUCCESS)
CPU: 1.985s

Apr 24 01:00:12 V-CONT-02 python3[1255]:
Apr 24 01:00:12 V-CONT-02 python3[1255]:
Apr 24 01:00:12 V-CONT-02 python3[1255]: [INFO] - CRATE is running in localhost backup mode.
Apr 24 01:00:12 V-CONT-02 python3[1255]: [INFO] - Testing source dir is readable...
Apr 24 01:00:12 V-CONT-02 python3[1255]: [FATAL ERROR] - The following file(s) are unreadable:
Apr 24 01:00:12 V-CONT-02 python3[1255]: /containers/v-cont-02/data/jamesmaple.co.uk/db/mysql.sock
Apr 24 01:00:12 V-CONT-02 python3[1255]: /containers/v-cont-02/data/wordpress/wordpress/db/mysql.sock
Apr 24 01:00:12 V-CONT-02 python3[1255]: Program will now exit
Apr 24 01:00:12 V-CONT-02 systemd[1]: crate.service: Deactivated successfully.
Apr 24 01:00:12 V-CONT-02 systemd[1]: crate.service: Consumed 1.985s CPU time.
root@V-CONT-02:~#`