feat(logger): allow compiling out `espp::Logger` levels / verbosity to reduce size

Description

Add logger/Kconfig configuration allowing configuration of ESPP Logger max log level, which defaults to 4 (all logs compiled in)
Update espp::Logger to compile out the implementations of the various log functions depending on whether the config has enabled them.

Motivation and Context

As a system moves to production (or reaches the end of its partition size 😅), it may be necessary to optimize out log levels that are not being used so they do not contribute to code size.

How has this been tested?

Building and running logger/example on a QtPy ESP32s3 and compiling it with log level 4 (ALL) enabled, as well as compiling and running it with log level 2 (only errors and warnings). Checked that the compiled out logs did not print and that the resultant binary was smaller.

Screenshots (if appropriate, e.g. schematic, board, console logs, lab pictures):

New Menuconfig: CleanShot 2024-07-03 at 13 34 49

Execution with only warn and error compiled in: CleanShot 2024-07-03 at 13 33 15

Size with all logs: CleanShot 2024-07-03 at 13 34 11

Size with only error and warn logs: CleanShot 2024-07-03 at 13 31 54

That's a savings of ~31 kB, just by compiling out debug and info logs!

Types of changes

[ ] Bug fix (non-breaking change which fixes an issue)
[x] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
[x] Documentation Update
[ ] Hardware (schematic, board, system design) change
[x] Software change

Checklist:

[x] My change requires a change to the documentation.
[x] I have added / updated the documentation related to this change via either README or WIKI

Software

[ ] I have added tests to cover my changes.
[ ] I have updated the .github/workflows/build.yml file to add my new test to the automated cloud build github action.
[x] All new and existing tests passed.
[x] My code follows the code style of this project.

esp-cpp / espp