fix: align native mixed audio timeline

scripts/test-windows-wgc-helper.mjs

@@ -1,4 +1,5 @@
 import { spawn, spawnSync } from "node:child_process";
+import { randomUUID } from "node:crypto";
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
@@ -105,7 +106,7 @@ if (!fs.existsSync(HELPER_PATH)) {
 
 const outputPath = path.join(
 	os.tmpdir(),
-	`openscreen-wgc-helper-${WITH_SYSTEM_AUDIO || WITH_MICROPHONE ? "audio" : "video"}-${Date.now()}.mp4`,
+	`openscreen-wgc-helper-${WITH_SYSTEM_AUDIO || WITH_MICROPHONE ? "audio" : "video"}-${process.pid}-${Date.now()}-${randomUUID()}.mp4`,
 );
 
 const config = {