Remove Settings and Setup pages along with their tests and related API services

- Deleted Settings.tsx and Setup.tsx pages, which included functionality for changing passwords and setting up an admin account.
- Removed associated test files for Setup page.
- Eliminated API service definitions related to proxy hosts, remote servers, import functionality, and health checks.
- Cleaned up mock data and test setup files.
- Removed configuration files for TypeScript, Vite, and Tailwind CSS.
- Deleted scripts for testing coverage, release management, Dockerfile validation, and Python compilation checks.
- Removed Sourcery pre-commit wrapper script.

frontend/src/components/ThemeToggle.tsx

@@ -1,12 +0,0 @@
-import { useTheme } from '../context/ThemeContext'
-import { Button } from './ui/Button'
-
-export function ThemeToggle() {
-  const { theme, toggleTheme } = useTheme()
-
-  return (
-    <Button variant="ghost" size="sm" onClick={toggleTheme} title={`Switch to ${theme === 'dark' ? 'light' : 'dark'} mode`}>
-      {theme === 'dark' ? '☀️' : '🌙'}
-    </Button>
-  )
-}