feat: 完善架构优化性能

- 调整音视频架构，提升 RKMPP 编码 MJPEG-->H264 性能，同时解决丢帧马赛克问题；
- 删除多用户逻辑，只保留单用户，支持设置 web 单会话；
- 修复删除体验不好的的回退逻辑，前端页面菜单位置微调；
- 增加 OTG USB 设备动态调整功能；
- 修复 mdns 问题，webrtc 视频切换更顺畅。

src/audio/mod.rs

@@ -6,7 +6,6 @@
 //! - Audio device enumeration
 //! - Audio streaming pipeline
 //! - High-level audio controller
-//! - Shared audio pipeline for WebRTC multi-session support
 //! - Device health monitoring
 
 pub mod capture;
@@ -14,7 +13,6 @@ pub mod controller;
 pub mod device;
 pub mod encoder;
 pub mod monitor;
-pub mod shared_pipeline;
 pub mod streamer;
 
 pub use capture::{AudioCapturer, AudioConfig, AudioFrame};
@@ -22,7 +20,4 @@ pub use controller::{AudioController, AudioControllerConfig, AudioQuality, Audio
 pub use device::{enumerate_audio_devices, enumerate_audio_devices_with_current, AudioDeviceInfo};
 pub use encoder::{OpusConfig, OpusEncoder, OpusFrame};
 pub use monitor::{AudioHealthMonitor, AudioHealthStatus, AudioMonitorConfig};
-pub use shared_pipeline::{
-    SharedAudioPipeline, SharedAudioPipelineConfig, SharedAudioPipelineStats,
-};
 pub use streamer::{AudioStreamState, AudioStreamer, AudioStreamerConfig};