Function validate_config 

pub async fn validate_config(
    project_dir: &Path,
    lockfile: &LockFile,
    gitignore_enabled: bool,
) -> ConfigValidation

Validate project configuration for AGPM.

Checks:

1. Required .gitignore entries based on installed resource types (if gitignore_enabled)

Note: Claude Code settings check is intentionally not performed here. The /config guidance is only shown during init and migrate commands to avoid repetitive warnings on every install/update.

Arguments

• project_dir - Path to the project directory
• lockfile - The lockfile containing installed resources
• gitignore_enabled - Whether gitignore validation is enabled (from manifest)