fix(auth): harden unified diagnostic execution

tools/tht/internal/compose/process_unix.go

@@ -0,0 +1,37 @@
+//go:build !windows
+
+package compose
+
+import (
+	"errors"
+	"os/exec"
+	"syscall"
+	"time"
+)
+
+const gracefulTerminationBound = 500 * time.Millisecond
+const finalTerminationBound = 2 * time.Second
+
+func configureProcess(command *exec.Cmd) {
+	command.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
+}
+
+func terminateProcess(command *exec.Cmd, done <-chan error) error {
+	if command.Process == nil {
+		return nil
+	}
+	_ = syscall.Kill(-command.Process.Pid, syscall.SIGINT)
+	select {
+	case <-done:
+		return nil
+	case <-time.After(gracefulTerminationBound):
+	}
+	_ = syscall.Kill(-command.Process.Pid, syscall.SIGKILL)
+	_ = command.Process.Kill()
+	select {
+	case <-done:
+		return nil
+	case <-time.After(finalTerminationBound):
+		return errors.New("Docker command could not be reaped")
+	}
+}