Feat: Add watch mode for working with content

[joe-watkins]

Add an npm script runner to manage development tasks.

Proposed script: npm run content:watch

Configure it to:

• Start the development server with npm start.
• Watch for changes in markdown files within the /public/content folder.
• Automatically run npm run parse-md-files when changes are detected (removing the need for manual execution).
• Ensure the browser reloads automatically after each build to reflect updates.
• Update Readme.md