Refactor generate-seo-files.mjs: Implement CLI Option Parsing with Commander

The buildScripts/generate-seo-files.mjs script currently parses command-line options manually using process.argv. This approach is inconsistent with other build scripts in the project, such as buildScripts/buildAll.mjs, which leverage the commander library for CLI argument parsing.

This ticket proposes to refactor buildScripts/generate-seo-files.mjs to use the commander library for handling its command-line options.

Benefits of using commander:

• Consistency: Aligns with existing project conventions for CLI tools.
• Robustness: Provides built-in argument validation and type checking.
• Maintainability: Reduces boilerplate code for argument parsing.
• User Experience: Automatically generates help messages and handles common CLI patterns.

Implementation Details:

• Replace the manual process.argv parsing logic within the runCli function with commander's API.
• Define all existing options (--format, --base-url, --base-path, --output, --no-lastmod, --no-top-level) using program.option().
• Ensure that the script's functionality remains identical after the refactoring.

Acceptance Criteria:

• buildScripts/generate-seo-files.mjs uses commander for CLI option parsing.
• All existing command-line options are supported and function as before.
• The script's output and behavior are unchanged when invoked with the same arguments.