feat: service worker preload scripts for improved extensions support (#44411)

* feat: preload scripts for service workers

* feat: service worker IPC

* test: service worker preload scripts and ipc

docs/api/service-worker-main.md

@@ -15,6 +15,19 @@ _This class is not exported from the `'electron'` module. It is only available a
 
 Returns `boolean` - Whether the service worker has been destroyed.
 
+#### `serviceWorker.send(channel, ...args)` _Experimental_
+
+- `channel` string
+- `...args` any[]
+
+Send an asynchronous message to the service worker process via `channel`, along with
+arguments. Arguments will be serialized with the [Structured Clone Algorithm][SCA],
+just like [`postMessage`][], so prototype chains will not be included.
+Sending Functions, Promises, Symbols, WeakMaps, or WeakSets will throw an exception.
+
+The service worker process can handle the message by listening to `channel` with the
+[`ipcRenderer`](ipc-renderer.md) module.
+
 #### `serviceWorker.startTask()` _Experimental_
 
 Returns `Object`:
@@ -25,6 +38,10 @@ Initiate a task to keep the service worker alive until ended.
 
 ### Instance Properties
 
+#### `serviceWorker.ipc` _Readonly_ _Experimental_
+
+An [`IpcMainServiceWorker`](ipc-main-service-worker.md) instance scoped to the service worker.
+
 #### `serviceWorker.scope` _Readonly_ _Experimental_
 
 A `string` representing the scope URL of the service worker.
@@ -32,3 +49,6 @@ A `string` representing the scope URL of the service worker.
 #### `serviceWorker.versionId` _Readonly_ _Experimental_
 
 A `number` representing the ID of the specific version of the service worker script in its scope.
+
+[SCA]: https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm
+[`postMessage`]: https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage