feat: rename WHM→NixServer, cPanel→NixClient, bump v0.2.0

- Rename frontend workspaces: whm/ → nixserver/, cpanel/ → nixclient/
- Rename server route dirs: routes/whm/ → routes/nixserver/, routes/cpanel/ → routes/nixclient/
- Update all API prefixes: /api/whm → /api/nixserver, /api/cpanel → /api/nixclient
- Rename env vars: WHM_PORT → NIXSERVER_PORT, CPANEL_PORT → NIXCLIENT_PORT
- Update config properties: whmPort → nixserverPort, cpanelPort → nixclientPort
- Update all UI labels, login pages, sidebar branding, and error messages
- Update installer and update scripts to match new names
- Add cpanel email route (missing from initial scaffold)
- Add .gitattributes to enforce LF line endings
- Bump version to 0.2.0 across all package.json files

nixclient/vite.config.ts

@@ -0,0 +1,17 @@
+import { defineConfig } from 'vite'
+import react from '@vitejs/plugin-react'
+import path from 'path'
+
+export default defineConfig({
+  plugins: [react()],
+  resolve: {
+    alias: { '@': path.resolve(__dirname, './src') },
+  },
+  server: {
+    port: 5174,
+    proxy: {
+      '/api': { target: 'http://localhost:2087', changeOrigin: true },
+      '/ws': { target: 'ws://localhost:2087', ws: true },
+    },
+  },
+})