Default to a module worker to fix import.meta crash under

GitOrigin-RevId: 304bed40eefd1ecb08e0c579bdb8be96b3e17dc7

Author: ibesora

src/util/web_worker.ts

@@ -2,5 +2,13 @@ import WorkerClass from './worker_class';
 
 export function createWorker(name?: string): Worker {
     // eslint-disable-next-line new-cap
-    return WorkerClass.workerClass != null ? new WorkerClass.workerClass() : new self.Worker(WorkerClass.workerUrl, ({name, ...WorkerClass.workerParams}));
+    if (WorkerClass.workerClass != null) return new WorkerClass.workerClass();
+    // The worker bundle is valid as classic or module, but only the
+    // module form permits `import.meta`. Downstream bundlers (Vite, Rolldown,
+    // webpack5+) instrument every dynamic import() they see by injecting
+    // `import.meta.url`.
+    // In a classic worker that throws "Cannot use 'import.meta' outside a module"
+    // the instant it parses, killing the worker silently while the main thread keeps
+    // running normally.
+    return new self.Worker(WorkerClass.workerUrl, ({name, type: 'module', ...WorkerClass.workerParams}));
 }