feat: initial commit - Supervisor UI with Next.js 16 and Tailwind CSS 4

- Modern web interface for Supervisor process management
- Built with Next.js 16 (App Router) and Tailwind CSS 4
- Full XML-RPC client implementation for Supervisor API
- Real-time process monitoring with auto-refresh
- Process control: start, stop, restart operations
- Modern dashboard with system status and statistics
- Dark/light theme with OKLCH color system
- Docker multi-stage build with runtime env var configuration
- Gitea CI/CD workflow for automated builds
- Comprehensive documentation (README, IMPLEMENTATION, DEPLOYMENT)

Features:
- Backend proxy pattern for secure API communication
- React Query for state management and caching
- TypeScript strict mode with Zod validation
- Responsive design with mobile support
- Health check endpoint for monitoring
- Non-root user security in Docker

Environment Variables:
- SUPERVISOR_HOST, SUPERVISOR_PORT
- SUPERVISOR_USERNAME, SUPERVISOR_PASSWORD (optional)
- Configurable at build-time and runtime

🤖 Generated with Claude Code (https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

components/providers/Providers.tsx

@@ -0,0 +1,30 @@
+'use client';
+
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
+import { useState, ReactNode } from 'react';
+import { Toaster } from 'sonner';
+import { ThemeProvider } from './ThemeProvider';
+
+export function Providers({ children }: { children: ReactNode }) {
+  const [queryClient] = useState(
+    () =>
+      new QueryClient({
+        defaultOptions: {
+          queries: {
+            staleTime: 3 * 1000, // 3 seconds for real-time feel
+            refetchOnWindowFocus: false,
+            retry: 2,
+          },
+        },
+      })
+  );
+
+  return (
+    <ThemeProvider>
+      <QueryClientProvider client={queryClient}>
+        {children}
+        <Toaster position="top-right" richColors closeButton />
+      </QueryClientProvider>
+    </ThemeProvider>
+  );
+}