refactor: Unified all UI colors, added reusable components. Removed Lightmode

[michelroegl-brunner]

Summary

This PR implements a comprehensive UI refactoring that removes execution_mode dependencies, aligns components with the new Button component, removes dark mode functionality, and standardizes colors using globals.css.

Major Changes Made

Execution Mode Refactoring

• ✅ Removed ExecutionModeBadge import and usage
• ✅ Updated filtering logic to use server_name presence instead of execution_mode
• ✅ Simplified update script logic by removing mode property
• ✅ Updated Terminal component call to determine mode based on server presence
• ✅ Replaced ExecutionModeBadge in table with simple text display
• ✅ Maintained backend API compatibility by keeping execution_mode in mutations
• ✅ Used nullish coalescing operator (??) for better null handling

UI Component Alignment

• ✅ Aligned all components with the new unified Button component
• ✅ Replaced custom button implementations with standardized Button component
• ✅ Ensured consistent button styling across all components

Dark Mode Removal

• ✅ Removed DarkModeProvider component
• ✅ Removed DarkModeToggle component
• ✅ Cleaned up dark mode related state management
• ✅ Simplified theme handling

Color Standardization

• ✅ Removed all hardcoded colors in favor of CSS variables from globals.css
• ✅ Updated components to use semantic color tokens
• ✅ Ensured consistent color scheme across the application
• ✅ Improved maintainability through centralized color management

Additional Improvements

• ✅ Added new UI components (ui/button.tsx, lib/utils.ts)
• ✅ Removed unused components (ProxmoxCheck.tsx)
• ✅ Updated package dependencies
• ✅ Enhanced TypeScript configuration

Technical Details

The refactoring simplifies the codebase by:

• Automatically determining execution mode based on server presence
• Using a unified design system with consistent components
• Centralizing color management through CSS variables
• Removing unnecessary complexity from theme switching

Files Changed

• 31 files modified with 1,117 additions and 849 deletions
• New components: ui/button.tsx, lib/utils.ts
• Removed components: DarkModeProvider.tsx, DarkModeToggle.tsx, ProxmoxCheck.tsx
• Updated: All major UI components for consistency

Testing

• All linting errors resolved
• Components render correctly with new design system
• Filtering works as expected
• Update functionality works for both local and SSH modes
• Add script functionality works correctly
• Color scheme is consistent across all components
• Button components work uniformly throughout the app