Make tracing more user-friendly

[filiptibell]

Summary

This PR makes a couple changes to tracing in Rokit:

• Adds a new --verbose flag to the CLI, making debugging Rokits behavior much more straightforward for a normal user. This flag may be specified twice for extra verbose logging with even more information.
• Removes the directly user-facing warning when a direct tool artifact match is not found, in favor of tracing messages that can be enabled with the new --verbose flag.
• Fixes the tracing level of some internal mechanisms such as executable parsing being set too high.

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Implementation note

The new --verbose flag is unfortunately order-dependent, meaning that this works:

• rokit --verbose install

... while this does not:

• rokit install --verbose

I didn't find any way around this using clap, or at least when using derive macros. It shouldn't be too much of an issue in practice but it is something to keep in mind.