DEVX-153: fix: run molecule destroy on test failure to clean up containers

src/devx/molecule/molecule_ci_guard.py

@@ -246,18 +246,62 @@ def cli(pairs: tuple[str, ...], roles_root: Path | None) -> None:
                             with contextlib.suppress(ProcessLookupError):
                                 os.killpg(os.getpgid(process.pid), signal.SIGKILL)
                             process.wait()
+                        # Clean up containers left behind by the killed test.
+                        click.echo(_("Cleaning up: running molecule destroy for {scenario}", scenario=scenario))
+                        destroy_cmd = ["molecule", "destroy"]
+                        if scenario != "default":
+                            destroy_cmd.extend(["-s", scenario])
+                        with contextlib.suppress(subprocess.SubprocessError, OSError):
+                            subprocess.run(  # nosec B603, B607
+                                destroy_cmd,
+                                cwd=str(cwd),
+                                env=env,
+                                check=False,
+                                capture_output=True,
+                                timeout=120,
+                            )
                         sys.exit(1)
                     time.sleep(1)
             except KeyboardInterrupt:
                 with contextlib.suppress(ProcessLookupError):
                     os.killpg(os.getpgid(process.pid), signal.SIGTERM)
                 process.wait()
+                # Clean up containers left behind by the interrupted test.
+                click.echo(_("Cleaning up: running molecule destroy for {scenario}", scenario=scenario))
+                destroy_cmd = ["molecule", "destroy"]
+                if scenario != "default":
+                    destroy_cmd.extend(["-s", scenario])
+                with contextlib.suppress(subprocess.SubprocessError, OSError):
+                    subprocess.run(  # nosec B603, B607
+                        destroy_cmd,
+                        cwd=str(cwd),
+                        env=env,
+                        check=False,
+                        capture_output=True,
+                        timeout=120,
+                    )
                 sys.exit(1)
 
             rc = process.returncode
 
             if rc != 0:
                 click.echo(_("FAILED: {pair} exited with code {code}", pair=pair, code=rc))
+                # Run molecule destroy to clean up containers left behind by the
+                # failed test. Without this, containers stay running and accumulate
+                # on the runner, consuming disk/memory and degrading CI performance.
+                click.echo(_("Cleaning up: running molecule destroy for {scenario}", scenario=scenario))
+                destroy_cmd = ["molecule", "destroy"]
+                if scenario != "default":
+                    destroy_cmd.extend(["-s", scenario])
+                with contextlib.suppress(subprocess.SubprocessError, OSError):
+                    subprocess.run(  # nosec B603, B607
+                        destroy_cmd,
+                        cwd=str(cwd),
+                        env=env,
+                        check=False,
+                        capture_output=True,
+                        timeout=120,
+                    )
                 sys.exit(rc)
 
             click.echo(_("PASSED: {pair}", pair=pair))