Module path_validation 

Path validation helpers for CLI commands.

cli-error-clarity-v2 (P2.BUG-4): commands that operate on a project directory (hubs, impact, whatbreaks, change-impact, …) historically produced confusing errors when given a regular file:

• tldr hubs <file> → Error: Path not found: <file> (false: it exists)
• tldr change-impact <file> → Git: Not a directory (os error 20) (cryptic; the user has no idea what to do)

These helpers normalise the validation so every directory-taking command returns the same clear, actionable error mentioning the file path and suggesting the project root.

All helpers return anyhow::Error so they can be used directly with the ? operator inside run() methods that already return anyhow::Result<()>.

Functions

require_directory

Validate that path exists and is a directory, producing clear error messages on failure.