Add --version / -v flag to display version

[xmha97]

Description

Currently, there is no straightforward way to check the version of the CLI tool from the command line.

neon@neon:~/Downloads/terminal/dnstt/bin$ ./dnstt --version 2>&1 | head -n 1
flag provided but not defined: -version
neon@neon:~/Downloads/terminal/dnstt/bin$ ./dnstt -v 2>&1 | head -n 1
flag provided but not defined: -v

Expected Behavior

It would be helpful to support a standard flag such as:

• --version
• -v

These flags should print the current version of the tool and exit.

Why this is useful

• Aligns with common CLI conventions
• Helps with debugging and reporting issues
• Improves usability for users and developers

Example

$ dnstt --version
dnstt 1.2.3

Additional Context

Many CLI tools follow this convention, so adding it would improve consistency and user experience.

[xmha97]

Add also for findns and slipstream