Common Directory, Formatting and Added Intent

[okBrian]

Description

Formatting Changes and Added Intent to the Common Directory Only
Next is pre_process, sim, and post-process
Fixes #477

Type of change

• Something else

Scope

• This PR comprises a set of related changes with a common goal

How Has This Been Tested?

• Builds and Runs without Errors with Github Actions
• Builds and Runs on local machine

Test Configuration:
Ubuntu 22.04.4 LTS, gcc 14

Checklist

• I ran ./mfc.sh format before committing my code
• New and existing tests pass locally with my changes, including with GPU capability enabled (both NVIDIA hardware with NVHPC compilers and AMD hardware with CRAY compilers) and disabled
• This PR does not introduce any repeated code (it follows the DRY principle)
• I cannot think of a way to condense this code and reduce any introduced additional line count