test(terminal): keep the argv test child alive through its assertion

The POSIX argv test reads the terminal screen while its child can exit and dispose the parser. Keep the child alive until the assertion completes, as other screen tests do, and let the existing session cleanup terminate it.

Co-authored-by: Dominic Anaeto <dominic.anaeto@gmail.com>

packages/server/src/terminal/terminal.test.ts

@@ -410,7 +410,12 @@ describe("createTerminal", () => {
           cwd: realpathSync(tmpdir()),
           cols: 500,
           command: process.execPath,
-          args: ["-e", "process.stdout.write(JSON.stringify(process.argv.slice(1)))", nastyPrompt],
+          // Keep the PTY alive until the screen assertion; exit disposes its parser.
+          args: [
+            "-e",
+            "process.stdout.write(JSON.stringify(process.argv.slice(1))); setInterval(() => {}, 100000)",
+            nastyPrompt,
+          ],
         }),
       );