Add osu! (Debug, Second Client) launch option for VS Code (#37197)

Kinda self explanatory, adds a second client configurations so its
easier to test multiplayer-specific things when using VSCode

For people that don't know how to use this, basically just run the first
debug like normal, then swap to the second client option and run that.
You can also do it in reverse. Visual guide here:

https://github.com/user-attachments/assets/1dab50eb-3bd2-422d-a776-852ac4454213

.vscode/launch.json

@@ -13,6 +13,19 @@
             "preLaunchTask": "Build osu! (Debug)",
             "console": "internalConsole"
         },
+        {
+            "name": "osu! (Debug, Second Client)",
+            "type": "coreclr",
+            "request": "launch",
+            "program": "dotnet",
+            "args": [
+                "${workspaceRoot}/osu.Desktop/bin/Debug/net8.0/osu!.dll",
+                "--debug-client-id=1"
+            ],
+            "cwd": "${workspaceRoot}",
+            "preLaunchTask": "Build osu! (Debug)",
+            "console": "internalConsole"
+        },
         {
             "name": "osu! (Release)",
             "type": "coreclr",