Move panel temporary state to worker OPFS

web/worker/sim-worker.mjs

@@ -1,12 +1,14 @@
 import createModule from "../../build-wasm/linuxcnc-sim-core.js";
 import { XyzacSession } from "./xyzac-session.mjs";
+import { handleWorkerMessage } from "./opfs-worker-bridge.mjs";
 
 const core = await createModule();
 const session = new XyzacSession(core, { planner: "linuxcnc-tp" });
 
-self.onmessage = (event) => {
+let serial = Promise.resolve();
+self.onmessage = (event) => { serial = serial.then(async () => {
   try {
-    self.postMessage(session.accept(event.data));
+    self.postMessage(await handleWorkerMessage(session, event.data));
   } catch (error) {
     self.postMessage({
       schema_version: 1,
@@ -17,4 +19,5 @@ self.onmessage = (event) => {
       payload: { status: "error", code: "worker_exception", message_key: String(error?.message ?? error), retryable: false },
     });
   }
+});
 };