Update Pre-Week Checklist and Lab 0 Setup documentation for clarity and accuracy

[will0684]

This pull request updates the onboarding documentation for Lab 0 to clarify the required setup steps and the contents of the initial README file. The most important changes focus on making instructions more explicit for verifying local environment setup and standardizing what is expected in the lab submission.

Improvements to setup verification and instructions:

• Updated the pre-week checklist in PRE_WEEK_CHECKLIST.md to require running version commands (mvn -v, node -v, npm -v) instead of full build/test commands, making it easier for new users to confirm their environment is ready.
• Clarified the steps in LAB_0_SETUP.md to explicitly require creating a new README.md file in the working directory, and specified what should be included in the README for Lab 0 submissions.
• Updated the required contents of README.md to include verification commands from the pre-week checklist and a brief description of lab actions, improving consistency and clarity for submissions.

General documentation improvements:

• Added comments to highlight confusing or unnecessary instructions, making it easier for future maintainers to further refine the onboarding docs. [1] [2]