Adjust button alignment and layout in EssentialsInitializerWindow

[Sugar0612]

This pull request refines the layout of the EssentialsInitializerWindow to improve the alignment and visual consistency of UI elements. Key changes include:

• The "Install" button is now centered vertically and aligned with the "Essentials Services" text.
• The Ready status is left-aligned with the title for better visual coherence.
• A compact toolbar style has been applied to the header for a more unified appearance.
• The height and padding of the dependency list items have been standardized, ensuring consistent spacing and alignment throughout the window.
• The color of the "Installed" text has been adjusted to a more natural green.

These adjustments enhance the overall user experience by creating a cleaner and more organized interface.