[FEAT] Set log_level via environment variables

[instantdreams]

Feature Description
I wish to be able to adjust the log level of Scrutiny (web, collector, omnibus, doesn't matter) using environment variables (for docker) or flags (for bare metal).

At the moment, creating a scrutiny.yaml file with the following entries works but is clunky when I wish to keep my configuration in environment variables only:

version: 1
log:
  file: ''
  level: WARN

Feature Solution
Implement variable SCRUTINY_LOG_LEVEL with the usual enums of Trace, Debug, Info, Warn, Error, Critical, None or similar as supported by Scrutiny application. Apply a similar flag to the command line of --log-level.

Variable SCRUTINY_LOG_LEVEL to apply to all flavours of Scrutiny - omnibus, web, collector - and restrict the output to the appropriate level.

Additional Context
A list of all environment variables would be useful for the docs section, too!