[feat] update some feature

sync code of  fastrtc,
add text support through datachannel,
fix safari connect problem
support chat without camera or mic

demo/whisper_realtime/README_gradio.md

@@ -0,0 +1,22 @@
+---
+app_file: app.py
+colorFrom: purple
+colorTo: red
+emoji: 👂
+license: mit
+pinned: false
+sdk: gradio
+sdk_version: 5.16.0
+short_description: Transcribe audio in realtime - Gradio UI version
+tags:
+- webrtc
+- websocket
+- gradio
+- secret|TWILIO_ACCOUNT_SID
+- secret|TWILIO_AUTH_TOKEN
+- secret|GROQ_API_KEY
+title: Whisper Realtime Transcription (Gradio UI)
+---
+
+
+Check out the configuration reference at https://huggingface.co/docs/hub/spaces-config-reference