Pass derivation details through from Rust.

[benjyw]

This allows us to specify which config file each value came from.

We intern the details strings, as they are very repetitive. This requires tying the lifetime of various data structures to that of the GIL.

[benjyw]

Easiest reading order for review:

• src/python/pants/engine/internals/native_engine.pyi
• src/rust/engine/src/externs/options.rs
• src/python/pants/option/native_options.py
• src/python/pants/help/help_info_extracter.py
• src/python/pants/help/help_info_extracter_test.py

Thanks!