Fix: incorrect type in lib/html_utility.php and display_help format

[TheWitness]

No description provided.

[Copilot]

Pull request overview

This PR corrects a PHP type declaration mismatch and aligns CLI helper naming/behavior, while also adjusting pre-commit hook scope.

Changes:

• Update validate_is_regex() return type from true|string to bool|string to match supported PHP typing.
• Rename displayVersion()/displayHelp() to display_version()/display_help() in cli/add_site.php and adjust error/help output flow.
• Remove the files: ^app/ restriction from local pre-commit hooks so they run more broadly.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
lib/html_utility.php	Fixes the return type declaration/docblock for validate_is_regex() to use a supported union type.
cli/add_site.php	Standardizes helper function names to snake_case and refactors how help/error output is produced.
.pre-commit-config.yaml	Broadens when hooks trigger by removing the file filter.