feat: implement real-time update progress with proper theming

[michelroegl-brunner]

🚀 Real-time Update Progress Implementation

This PR implements a comprehensive real-time update progress system that keeps the modal open until the server restarts after an update.

✨ Features

Real-time Log Streaming:

• Polling-based approach (1-second intervals) instead of WebSocket subscriptions
• ANSI color code stripping for clean log display
• Terminal-style output with proper dark mode support
• Auto-scrolling log display

Smart Completion Detection:

• Detects specific completion indicators in logs:
  • Service enabled and started successfully
  • Service is running
  • Update completed successfully
• Only triggers reconnection when update is actually complete

Conservative Fallback Logic:

• Waits at least 3 minutes before considering fallback reconnection
• Requires 60 seconds of log silence before assuming server restart
• Prevents premature modal closing during dependency installation

Improved Theming:

• Fixed CSS specificity issues with !important for bg-card class
• Updated all colors to use CSS variables for consistency
• Proper dark mode support throughout the modal
• Terminal-style log output with dark background and green text

🔧 Technical Changes

Backend (version.ts):

• Added getUpdateLogs query with completion detection
• Stripped ANSI codes from log output
• Enhanced completion indicators

Frontend (VersionDisplay.tsx):

• Replaced subscription with polling-based log fetching
• Added smart reconnection logic with timing controls
• Updated UI to use CSS variables
• Improved modal theming and layout

Styling (globals.css):

• Added !important to bg-card class for proper theming
• Ensured CSS variables take precedence over Tailwind defaults

🎯 User Experience

• Modal stays open during entire update process
• Real-time progress visibility
• No premature "server restarting" messages
• Automatic page reload when server comes back online
• Consistent theming with application design system

🧪 Testing

• Tested with full update cycle including dependency installation
• Verified proper completion detection
• Confirmed dark mode theming works correctly
• Validated reconnection logic timing