Refactor CLI entry point to use main() function

[marevol]

This update refactors the CLI entry point by introducing a main() function that calls app(). The if name == "main" block now invokes main() instead of calling app() directly. This change improves maintainability and allows the CLI to be executed programmatically from other modules without relying on the main check.

[Copilot]

Pull Request Overview

This PR refactors the CLI entry point to improve maintainability and programmatic access by introducing a main() function wrapper around the existing app() call. This follows Python packaging best practices for CLI applications.

• Introduces a new main() function that calls app()
• Updates the if __name__ == "__main__" block to call main() instead of app() directly

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[Copilot]

The main() function should include a docstring to document its purpose as the CLI entry point, especially since it's intended for programmatic use from other modules.

Suggested change

	def main():
	def main():
	"""
	CLI entry point for fessctl.
	This function invokes the Typer application and can be called programmatically
	from other modules to start the CLI.
	"""