Configuration documentation clarity

Ensure configuration documentation clearly and accurately describes environment variables, command-line flags, and their relationships. Pay special attention to precedence rules, equivalent options, and proper grammar when explaining configuration behavior.

Key areas to review:

• Verify environment variable names and their effects are correctly documented
• Clearly explain relationships between environment variables and command-line flags
• Document precedence rules (e.g., command-line flags override environment variables)
• Use consistent and grammatically correct language when describing configuration options

Example of good documentation:

# Clear precedence explanation
Setting the `COMPOSE_PROJECT_NAME` environment variable is equivalent to the `-p` flag,
and `COMPOSE_PROFILES` environment variable is equivalent to the `--profiles` flag.

If a flag is set via the command line, the associated environment variable is ignored.

This ensures developers understand exactly how different configuration methods interact and which takes precedence in various scenarios.