feat: implement media echo fix and YouTube screenshare design

- Introduced a new `ScreenShareController` to manage YouTube screenshare functionality.
- Updated `DiscordPlayer` to track ownership of audio streams, preventing conflicts between music playback and screenshare.
- Added error handling for various states including voice connection checks and media busy states.
- Created unit tests for `ScreenShareController` and `DiscordPlayer` ownership rules to ensure correct functionality.
- Added documentation for the new media echo fix and screenshare design.

src/media/ytdlp.ts

@@ -9,6 +9,7 @@ export interface YtDlpMetadata {
 export interface YtDlpClient {
   getMetadata(url: string): Promise<YtDlpMetadata>;
   getDirectAudioUrl(url: string): Promise<string>;
+  getDirectVideoUrl(url: string): Promise<string>;
 }
 
 export interface YtDlpDependencies {
@@ -49,6 +50,19 @@ export function createYtDlp(dependencies: YtDlpDependencies = {}): YtDlpClient {
       ]);
       return value.trim().split("\n")[0] || url;
     },
+
+    async getDirectVideoUrl(url: string): Promise<string> {
+      const value = await runYtDlp(spawn, [
+        url,
+        "--get-url",
+        "--format",
+        "bestvideo[protocol^=http]+bestaudio[protocol^=http]/best[protocol^=http]/best",
+        "--no-playlist",
+        "--no-warnings",
+        "--quiet",
+      ]);
+      return value.trim().split("\n")[0] || url;
+    },
   };
 }