docs: add documentation for ImageView (#46760)

* docs: Add documentation for ImageView

* docs: Add ImageView main process module list in README.md

* test: Add some basic tests for ImageView

* test: Fill out Window embedding tests to better reflect how someone might use an ImageView

* docs: Add notes about using ImageView as a splash screen

Co-authored-by: Niklas Wenzel <dev@nikwen.de>

* docs: Update ImageView example to show a more complete splash screen example

* docs: Remove view resizing logic since the ImageView automatically gets resized

---------

Co-authored-by: Niklas Wenzel <dev@nikwen.de>

docs/api/image-view.md

@@ -0,0 +1,61 @@
+# ImageView
+
+> A View that displays an image.
+
+Process: [Main](../glossary.md#main-process)
+
+This module cannot be used until the `ready` event of the `app`
+module is emitted.
+
+Useful for showing splash screens that will be swapped for `WebContentsView`s
+when the content finishes loading.
+
+Note that `ImageView` is experimental and may be changed or removed in the future.
+
+```js
+const { BaseWindow, ImageView, nativeImage, WebContentsView } = require('electron')
+const path = require('node:path')
+
+const win = new BaseWindow({ width: 800, height: 600 })
+
+// Create a "splash screen" image to display while the WebContentsView loads
+const splashView = new ImageView()
+const splashImage = nativeImage.createFromPath(path.join(__dirname, 'loading.png'))
+splashView.setImage(splashImage)
+win.setContentView(splashView)
+
+const webContentsView = new WebContentsView()
+webContentsView.webContents.once('did-finish-load', () => {
+  // Now that the WebContentsView has loaded, swap out the "splash screen" ImageView
+  win.setContentView(webContentsView)
+})
+webContentsView.webContents.loadURL('https://electronjs.org')
+```
+
+## Class: ImageView extends `View`
+
+> A View that displays an image.
+
+Process: [Main](../glossary.md#main-process)
+
+`ImageView` inherits from [`View`](view.md).
+
+`ImageView` is an [EventEmitter][event-emitter].
+
+### `new ImageView()` _Experimental_
+
+Creates an ImageView.
+
+### Instance Methods
+
+The following methods are available on instances of the `ImageView` class, in
+addition to those inherited from [View](view.md):
+
+#### `image.setImage(image)` _Experimental_
+
+* `image` NativeImage
+
+Sets the image for this `ImageView`. Note that only image formats supported by
+`NativeImage` can be used with an `ImageView`.
+
+[event-emitter]: https://nodejs.org/api/events.html#events_class_eventemitter