feat: voice mode

[phact]

This pull request introduces a new voice assistant feature to the application, including backend API support and frontend integration. The most important changes include adding the voice_mode_router, creating a new WebSocket endpoint for voice interactions, and implementing the frontend components for voice recording and playback.

Backend Changes:

• src/backend/base/langflow/api/router.py: Added voice_mode_router to the main API router. [1] [2]
• src/backend/base/langflow/api/v1/__init__.py: Imported and registered voice_mode_router. [1] [2]
• src/backend/base/langflow/api/v1/voice_mode.py: Created a new module for handling voice mode interactions, including WebSocket endpoints and functions for managing voice sessions.

Frontend Changes:

• src/frontend/src/components/VoiceAssistant/index.tsx: Implemented the VoiceAssistant component, which handles audio recording, WebSocket communication, and playback.
• src/frontend/src/components/VoiceAssistant/streamProcessor.ts: Added an AudioWorkletProcessor for processing audio streams.
• src/frontend/src/components/VoiceAssistant/utils.ts: Added utility functions for converting base64 audio data to Float32Array.
• src/frontend/src/modals/IOModal/components/chatView/chatInput/newChatInput.tsx: Integrated the VoiceAssistant component into the chat input view. [1] [2]
• src/frontend/src/modals/IOModal/index.tsx: Added the VoiceAssistant component to the I/O modal. [1] [2]

[codspeed-hq]

CodSpeed Performance Report

Merging #4642 will degrade performances by 26.37%

_{Comparing phact:voice_mode (c2f15fe) with main (2881346)}

Summary

❌ 2 regressions
✅ 13 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	phact:voice_mode	Change
❌	test_successful_run_with_input_type_any	205.6 ms	260.2 ms	-21%
❌	test_successful_run_with_input_type_text	205.7 ms	279.4 ms	-26.37%