fix(env, log)!: RUST_LOG and other envs parsing

[folex]

Description

• Fix parsing certain config fields of Array type from ENV variables.
• Fix RUST_LOG parsing: trim whitespaces
• Load RUST_LOG only once, I believe it was twice before (in main.rs and layers.rs). @gurinderu, wdyt?
• ⚠️ Crash if RUST_LOG is incorrect. @nahsi, wdyt?

Motivation

A lot of lists in config did not parse from ENV before. Tabs after newlines in RUST_LOG didn't parse.

Checklist

• The code follows the project's coding conventions and style guidelines.
• All tests related to the changes have passed successfully.
• Documentation has been updated to reflect the changes (if applicable).
• All new and existing unit tests have passed.
• I have self-reviewed my code and ensured its quality.
• I have added/updated necessary comments to aid understanding.

Reviewer Checklist

• Code has been reviewed for quality and adherence to guidelines.
• Tests have been reviewed and are sufficient to validate the changes.
• Documentation has been reviewed and is up to date.
• Any questions or concerns have been addressed.