feat: add history prune subcommand

[xvello]

Closes #1742 by implementing the new atuin history prune subcommand discussed in this issue. This command defaults to removing matching lines, which can be previewed via the --dry-run command flag.

TODO:

• tests: tested manually without sync. I am reusing the search --delete code path, so remote deletes should work? I'd like to add a black-box test in atuin/tests/ to add a few history entries then prune part of them, but is it desirable?
• confirmation prompt: we could add a confirmation prompt before we delete the entries. Are there similar prompts I could reuse? Feel free to directly push the code for it.
• documentation: in the https://github.com/atuinsh/docs repo?

Checks

• I am happy for maintainers to push small adjustments to this PR, to speed up the review cycle
• I have checked that there are no existing pull requests for the same thing

[ellie]

Excellent! Thank you!

If we could also get an update to the docs, that would be greatly appreciated 🙏

https://github.com/atuinsh/docs

[xvello]

If we could also get an update to the docs, that would be greatly appreciated 🙏

Done: atuinsh/docs#37