fix(desktop): session persistence — refresh/login/context/empty-content 4-bug fix

1. App.tsx: add restoreSession() call on startup to prevent redirect
   to login page after refresh (isRestoring guard + BootstrapScreen)
2. CloneManager: call syncAgents() after loadClones() to restore
   currentAgent and conversation history on app load
3. zclaw-memory: add get_or_create_session() so frontend session UUID
   is persisted directly — kernel no longer creates mismatched IDs
4. openai.rs: assistant message content must be non-empty for
   Kimi/Qwen APIs — replace empty content with meaningful placeholders

Also includes admin-v2 ModelServices unified page (merge providers +
models + API keys into expandable row layout)

admin-v2/vite.config.ts

@@ -1,9 +1,10 @@
 import { defineConfig } from 'vite'
 import react from '@vitejs/plugin-react'
+import tailwindcss from '@tailwindcss/vite'
 import path from 'path'
 
 export default defineConfig({
-  plugins: [react()],
+  plugins: [tailwindcss(), react()],
   resolve: {
     alias: {
       '@': path.resolve(__dirname, 'src'),