Keep Glass attached through target-worker shutdown

Early Platform.exit detached JavaFX while queued macOS activation callbacks still called Java. Close the owned example before terminating its JVM, make shutdown idempotent, and reject late preview work. Add real startup-cancellation regressions and native crash-report checks.

scripts/check-connected-workflow.py

@@ -8,6 +8,7 @@ import subprocess
 import tempfile
 import json
 import time
+from native_crashes import NativeCrashGuard
 
 ROOT = Path(__file__).resolve().parent.parent
 parser = argparse.ArgumentParser(description=__doc__)
@@ -16,6 +17,7 @@ parser.add_argument("--idea-home", required=True)
 args = parser.parse_args()
 logs = ROOT / "target/connected-workflow"
 logs.mkdir(parents=True, exist_ok=True)
+crashes = NativeCrashGuard(ROOT)
 classpath = os.pathsep.join([str(ROOT / "designer-standalone/target/test-classes"),
                             str(ROOT / "designer-standalone/target/classes"),
                             (ROOT / "designer-standalone/target/smoke-classpath.txt").read_text().strip()])
@@ -41,6 +43,9 @@ with tempfile.TemporaryDirectory(prefix="designer-connected-") as temporary:
                 run(host + "-" + mode, [Path(os.environ["JAVA_HOME"]) / "bin/java", "-cp", classpath,
                     "de.neitzel.fxdesigner.standalone.WorkflowSmoke", ROOT, args.target_java_home,
                     fixture, mode])
+                run("worker-lifecycle-" + mode, [Path(os.environ["JAVA_HOME"]) / "bin/java", "-cp", classpath,
+                    "de.neitzel.fxdesigner.standalone.WorkerLifecycleSmoke", ROOT, fixture])
+                crashes.check()
                 local = fixture / ".neitzel-fx-designer"
                 (local / "runtimes.json").write_text(json.dumps({"schemaVersion":"1.0","runtimes":{"java21":{"build":args.target_java_home,"target":args.target_java_home}}}))
                 tools = [ROOT / ("designer-" + name) / "target" / ("designer-" + name + "-0.1.0-SNAPSHOT.jar") for name in ("target-tools","contracts","preview-api")]
@@ -82,3 +87,5 @@ with tempfile.TemporaryDirectory(prefix="designer-connected-") as temporary:
                        "-PideaHome=" + args.idea_home, "-Ddesigner.workflow.fixtures=" + str(base),
                        "-Ddesigner.repository=" + str(ROOT), "-Ddesigner.target.java=" + args.target_java_home,
                        "test"])
+
+crashes.check()