update setup comments

deploy-examples/RWKV-Runner-WebUI/setup.bat

@@ -9,6 +9,7 @@ call npm ci
 call npm run build
 cd ..
 
+: optional: set ngrok_token=YOUR_NGROK_TOKEN
 start python ./backend-python/main.py --webui
 start "C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" "http://127.0.0.1:8000"
 

deploy-examples/RWKV-Runner-WebUI/setup.sh

@@ -11,6 +11,7 @@ npm ci
 npm run build
 cd ..
 
+# optional: export ngrok_token=YOUR_NGROK_TOKEN
 python3 ./backend-python/main.py --webui > log.txt & # this is only an example, you should use screen or other tools to run it in background
 
 if [ ! -d models ]; then