feat(admin-web): add Vue 3 admin console and deployment configs

- Add admin-web/ with Vite + Vue 3 + Element Plus + Vue Router
- Add 8 management pages: dashboard, channel subject/account, conversation,
  person, tag, send record (with test send), inbound flow
- Add API client modules for account/channel/crm/send/flow
- Add Dockerfile and nginx config for admin-web
- Add Dockerfile for mci-server
- Add docker-compose.app.yml for one-command app deployment
- Add K8s deployment manifests for backend/admin-web/channel-service
- Update scripts/local-up.sh with shared network and --with-apps option

admin-web/nginx.conf

@@ -0,0 +1,16 @@
+server {
+    listen 80;
+    server_name localhost;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+
+    location /msg-platform {
+        proxy_pass http://mci-server:8080;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+    }
+}