Fix alerts and prompts

• Expand the no KDK found alert to also show it when the KDK directory does not exist
• Fix alert ordering:
  • Restart prompt blocks and covers the success alert, preventing users from seeing the success message first. Show success message before restart prompt.

Link to KDKs repository

• Adjust KextSelectionView.swift UI and font styles
• Add a download link to the KDK Not Found warning box, pointing to the Dortania KDK repository

New app icon

Refactor project structure and update assets:

• Replaced app icon assets with new icons
• Removed SimpleLoaderResInstaller and related files
• Added new localized resources (ko, pt-BR)
• Updated README files (including new Spanish translation)
• Update .gitignore
• Removed unused files and references