Extract the `runner` module into its own crate

[saulecabrera]

This commit extracts the utiility runner module, used in the integration tests into its own private crate. The main motivation for this change is to enable sharing this functionality between integration tests and the upcoming javy-fuzz crate.

Additionally, this change promotes some dependencies to the workspace level, namely:

• tempfile
• uuid

Checklist

• [x] I've updated the relevant CHANGELOG files if necessary. Changes to javy-cli and javy-core do not require updating CHANGELOG files.
• [x] I've updated the relevant crate versions if necessary. Versioning policy for library crates
• [x] I've updated documentation including crate documentation if necessary.