Add CloudXR VR streaming support for PICO 4 Ultra (Early Access)

Replaces manual H264/TCP stereo streaming with NVIDIA CloudXR for
higher-quality stereoscopic rendering and lower latency.

Changes:
- teleop_xr_agent.py: add --cloudxr flag (enables Isaac Sim XR mode,
  disables manual StreamingManager)
- deps/cloudxr/: NVIDIA CloudXR.js SDK (Early Access) with Isaac Lab
  teleop React web client
- deps/cloudxr/Dockerfile.wss.proxy: HAProxy WSS proxy for PICO 4 Ultra
  HTTPS mode (routes wss://48322 → ws://49100)
- deps/cloudxr/isaac/webpack.dev.js: disable file watching to avoid
  EMFILE errors with large node_modules
- deps/cloudxr/INSTALL.md: full setup guide

Usage:
  # Start CloudXR Runtime + Isaac Lab
  cd ~/IsaacLab && ./docker/container.py start \
      --files docker-compose.cloudxr-runtime.patch.yaml \
      --env-file .env.cloudxr-runtime

  # Run teleop with CloudXR
  ~/IsaacLab/isaaclab.sh -p teleop_xr_agent.py \
      --task Isaac-MindRobot-2i-DualArm-IK-Abs-v0 --cloudxr

  # Serve web client
  cd deps/cloudxr/isaac && npm run dev-server:https

deps/cloudxr/simple/package.json

@@ -0,0 +1,31 @@
+{
+  "name": "cloudxr-simple-example",
+  "version": "6.0.0-beta",
+  "private": true,
+  "description": "CloudXR.js WebGL example application",
+  "author": "NVIDIA Corporation",
+  "license": "SEE LICENSE IN LICENSE",
+  "keywords": [],
+  "scripts": {
+    "build": "webpack --config ./webpack.prod.js",
+    "dev": "webpack --config ./webpack.dev.js",
+    "dev-server": "webpack serve --config ./webpack.dev.js --no-open",
+    "dev-server:https": "HTTPS=true webpack serve --config ./webpack.dev.js --no-open",
+    "clean": "rimraf build"
+  },
+  "dependencies": {
+    "@nvidia/cloudxr": "dev"
+  },
+  "devDependencies": {
+    "@types/node": "^22.13.14",
+    "@types/webxr": "^0.5.22",
+    "copy-webpack-plugin": "^13.0.0",
+    "gl-matrix": "^3.4.3",
+    "html-webpack-plugin": "^5.6.3",
+    "rimraf": "^5.0.5",
+    "ts-loader": "^9.5.1",
+    "typescript": "^5.8.2",
+    "webpack-dev-server": "^5.2.1",
+    "webpack-cli": "^6.0.1"
+  }
+}