🎨 Palette: [UX improvement] Dracula-themed Welcome Page

[christopherfoxjr]

This PR enhances the KibaOS welcome screen (embedded in build.sh) by transitioning it to a cohesive Dracula-inspired theme.

Key improvements:

• Visual Delight: Switched from a generic blue/white theme to the system-standard Dracula palette (#282a36, #bd93f9, etc.), providing a more professional and integrated first impression.
• Micro-UX: Added descriptive emojis (📖, 🐞, 🐙) to the primary action buttons to improve visual scannability and "personality".
• Accessibility:
  • Added aria-label attributes to icon-inclusive buttons.
  • Implemented :focus-visible styles with a clear purple outline to ensure keyboard-only users can navigate effectively.
  • Adjusted footer text contrast to meet WCAG AA standards by using a high-contrast foreground color with appropriate opacity instead of the low-contrast comment color.
• Hygiene: Removed trailing whitespace from build.sh to comply with repository audit standards.

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PR created automatically by Jules for task 1977568382191931702 started by @christopherfoxjr

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