add video to livekit calls

src/app/components/VoiceWidget.svelte

@@ -6,6 +6,8 @@
   import {displayRelayUrl} from "@welshman/util"
   import Microphone from "@assets/icons/microphone.svg?dataurl"
   import MicrophoneOff from "@assets/icons/microphone-off.svg?dataurl"
+  import Videocamera from "@assets/icons/videocamera.svg?dataurl"
+  import VideocameraRecord from "@assets/icons/videocamera-record.svg?dataurl"
   import PhoneRounded from "@assets/icons/phone-rounded.svg?dataurl"
   import PhoneCallingRounded from "@assets/icons/phone-calling-rounded.svg?dataurl"
   import CloseCircle from "@assets/icons/close-circle.svg?dataurl"
@@ -31,6 +33,7 @@
     voiceState,
     leaveVoiceRoom,
     toggleMute,
+    toggleCamera,
     cancelJoinVoiceRoom,
   } from "@app/voice"
 
@@ -107,9 +110,16 @@
           <Icon icon={$currentVoiceSession.muted ? MicrophoneOff : Microphone} size={4} />
         </Button>
         <Button
-          data-tip="Audio settings"
-          class="center tooltip tooltip-top btn btn-sm btn-square btn-ghost"
-          onclick={openAudioSettings}>
+          data-tip={$currentVoiceSession.cameraOn ? "Turn off camera" : "Turn on camera"}
+          class="center tooltip tooltip-top btn btn-sm btn-square {$currentVoiceSession.cameraOn
+            ? 'btn-ghost'
+            : 'btn-error'}"
+          onclick={toggleCamera}>
+          <Icon icon={$currentVoiceSession.cameraOn ? VideocameraRecord : Videocamera} size={4} />
+        </Button>
+        <Button>
+          data-tip="Audio settings" class="center tooltip tooltip-top btn btn-sm btn-square
+          btn-ghost" onclick={openAudioSettings}>
           <Icon icon={Settings} size={4} />
         </Button>
         <Button