外设管理

let cameras = meeting.getDevices(kind: .videoInput)
let microphones = meeting.getDevices(kind: .audioInput)
let speakers = meeting.getDevices(kind: .audioOutput)

let all = meeting.getDevices()   // 不传 kind 返回全部

// 指定设备
try await meeting.switchCamera(deviceId: deviceId)

// iOS 前后摄互切
try await meeting.switchCamera()

try meeting.switchMic(deviceId: deviceId)

try meeting.setAudioOutput(deviceId: deviceId)

try meeting.setSpeakerOutputEnabled(true)   // 强制外放
try meeting.setSpeakerOutputEnabled(false)  // 回到系统默认输出（听筒 / 蓝牙 / 有线耳机）

func meeting(_ meeting: SMeeting, didAddDevice data: DeviceChangeEventData) {
    refreshDeviceList()
}

func meeting(_ meeting: SMeeting, didRemoveDevice data: DeviceChangeEventData) {
    refreshDeviceList()
}

func refreshDeviceList() {
    cameras = meeting.getDevices(kind: .videoInput)
    if let id = selectedCameraId, !cameras.contains(where: { $0.deviceId == id }) {
        selectedCameraId = nil    // 回退到默认
    }
}