feat(gateway): restore Discord GoLive screenshare (dulu pernah ada, hilang saat split microservices)

User: 'dulu sharescreen juga bisa'. Terbukti: commit d50ce86 (Mei 2026)
punya src/media/screenShareController.ts + vendor @dank074/discord-video-stream,
hilang saat rombak monolith -> microservices. Interface ScreenShareController
masih ada di mediaTypes.ts tapi implementasinya tidak.

Restore:
- dep @dank074/discord-video-stream@6.0.0 (npm, dibangun untuk
  discord.js-selfbot-v13 — cocok dengan stack gateway)
- mediaSource.getDirectVideoUrl (yt-dlp --get-url bestvideo+bestaudio)
- screenShareController.ts (BARU): Streamer(client) + prepareStream H264
  720p30 + playStream go-live; owner check via discordPlayer
- media.handler: mode:'screen' di media:queue -> screen path; status
  expose activeMode; stop matiin screen
- FE: tombol Screen di MusicPlayer + hook useMediaQueue({url, mode})

Verifikasi: gateway tsc PASS, FE tsc PASS, biome 0 error, next build PASS.
Nix build pending (dep native @lng2004/node-datachannel butuh pnpm rebuild).

services/frontend/src/components/media/music-player.tsx

@@ -29,15 +29,19 @@ export function MusicPlayer({ ws }: MusicPlayerProps) {
   const stopMut = useMediaStop();
   const volumeMut = useMediaVolume();
   const [queueUrl, setQueueUrl] = useState("");
+  const [screenMode, setScreenMode] = useState(false);
 
   // Sync WS media_state into the query cache
   useMediaWsSync(ws);
 
   const handleQueue = useCallback(() => {
     if (!queueUrl.trim()) return;
-    queueMut.mutate(queueUrl.trim());
+    queueMut.mutate({
+      url: queueUrl.trim(),
+      mode: screenMode ? "screen" : "music",
+    });
     setQueueUrl("");
-  }, [queueUrl, queueMut]);
+  }, [queueUrl, queueMut, screenMode]);
 
   const handleVolume = useCallback(
     (value: number | readonly number[]) => {
@@ -64,6 +68,15 @@ export function MusicPlayer({ ws }: MusicPlayerProps) {
             onKeyDown={(e) => e.key === "Enter" && handleQueue()}
             className="flex-1 h-9"
           />
+          <Button
+            variant={screenMode ? "default" : "secondary"}
+            size="sm"
+            onClick={() => setScreenMode((v) => !v)}
+            title="Queue as Discord GoLive screenshare instead of audio playback"
+            className="h-9"
+          >
+            Screen
+          </Button>
           <Button
             onClick={handleQueue}
             disabled={!queueUrl.trim() || queueMut.isPending}
@@ -73,6 +86,14 @@ export function MusicPlayer({ ws }: MusicPlayerProps) {
           </Button>
         </div>
 
+        {mediaState?.activeMode && (
+          <p className="text-[10px] font-mono text-primary/80 uppercase tracking-wider">
+            {mediaState.activeMode === "screen"
+              ? "Screen share active"
+              : "Music playing"}
+          </p>
+        )}
+
         {mediaState?.current ? (
           <div className="rounded-lg bg-gradient-to-br from-primary/5 to-primary/[0.02] border border-primary/10 p-4 space-y-2">
             <p className="text-xs text-muted-foreground font-medium uppercase tracking-wider flex items-center gap-1.5">

services/frontend/src/hooks/use-media.ts

@@ -24,7 +24,10 @@ function useMediaAction<TArgs>(fn: (args: TArgs) => Promise<MediaState>) {
 }
 
 export function useMediaQueue() {
-  return useMediaAction((url: string) => mediaApi.queue(url, "music"));
+  return useMediaAction(
+    (input: { url: string; mode?: "music" | "screen" }) =>
+      mediaApi.queue(input.url, input.mode ?? "music"),
+  );
 }
 
 export function useMediaSkip() {

services/frontend/src/lib/types/media.ts

@@ -11,6 +11,7 @@ export interface MediaItem {
 
 export interface MediaState {
   playing: boolean;
+  activeMode?: MediaMode | null;
   musicVolume: number;
   current: MediaItem | null;
   queue: MediaItem[];