SDL: testaudio: Use SDL_SetAppMetadata at startup.

SDL Commits
1 
From 18a86ea6bbb4ce2576a4f424aa87a64931ae1cac Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Fri, 25 Apr 2025 13:01:47 -0400
Subject: [PATCH] testaudio: Use SDL_SetAppMetadata at startup.

This helps in finding its outputs in system lists of PipeWire streams, etc.
---
 test/testaudio.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/test/testaudio.c b/test/testaudio.c
index ce9f798c75791..459f3e3cfdc0f 100644
--- a/test/testaudio.c
+++ b/test/testaudio.c
@@ -1060,6 +1060,10 @@ SDL_AppResult SDL_AppInit(void **appstate, int argc, char *argv[])
 {
     int i;
 
+    char version[32];  /* use SDL's version number, since this test program is part of SDL's sources. */
+    SDL_snprintf(version, sizeof (version), "%d.%d.%d", SDL_MAJOR_VERSION, SDL_MINOR_VERSION, SDL_MICRO_VERSION);
+    SDL_SetAppMetadata("SDL testaudio", version, "org.libsdl.testaudio");
+
     state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO | SDL_INIT_AUDIO);
     if (!state) {
         return SDL_APP_FAILURE;