propose some changes to the Engines Vite docs

tests/dummy/app/templates/docs/embroider.md

@@ -1,36 +1,49 @@
 # Embroider Vite/Webpack
 
-Ember Engines is compatible with both webpack and vite variants of the embroider build system.  
-For more on the [Embroider](https://github.com/embroider-build/embroider) build system see the repository instructions on how to use it.  
-Engine specific changes when using Embroider:
-## Use strict `ember-resolver` (@^13.0.0)
-  ```diff
-  // addon/engine.js
-  import Engine from 'ember-engines/engine';
-  import Resolver from 'ember-resolver';
-  import loadInitializers from 'ember-load-initializers';
-  import config from './config/environment';
-  + import compatModules from '@embroider/virtual/compat-modules';
-
-  const { modulePrefix } = config;
-
-  class Eng extends Engine {
-  modulePrefix = config.modulePrefix;
-  - Resolver = Resolver;
-  + Resolver = Resolver.withModules(compatModules);
-  }
-
-  - loadInitializers(Eng, modulePrefix);
-  + loadInitializers(Eng, modulePrefix, compatModules);
-
-  export default Eng;
-  ```
+As of v0.13.0, Ember Engines is compatible with the new default Ember build system based on [Vite](https://vite.dev) and [Embroider](https://github.com/embroider-build/embroider). For your engines to work with Embroider you will need to make sure you are suing at least `ember-resolver@13.0.0` and you will need to update your `engine.js` entrypoint to pass `compatModules` to the resolver.
+
+This method of using the `ember-resolver` with `compatModules` is usually not compatible with the Classic build system but `ember-engines` automatically provides a polyfill so that an engine that has been updated to work with Embroider+Vite will continue to work with a Classic app that is still using `ember-cli` for its build.
+
+## How to update your `engine.js` entrypoint to support Embroider+Vite
+
+To support Embroider+Vite you need to first import `compatModules` from the virtual entrypoint `@embroider/virtual/compat-modules` and then pass it to your resolver using the `withModules()` function. You also need to pass `compatModules` to the `loadInitializers()` function.
+
+```diff
+// addon/engine.js
+import Engine from 'ember-engines/engine';
+import Resolver from 'ember-resolver';
+import loadInitializers from 'ember-load-initializers';
+import config from './config/environment';
++ import compatModules from '@embroider/virtual/compat-modules';
+
+const { modulePrefix } = config;
+
+class Eng extends Engine {
+modulePrefix = config.modulePrefix;
+- Resolver = Resolver;
++ Resolver = Resolver.withModules(compatModules);
+}
+
+- loadInitializers(Eng, modulePrefix);
++ loadInitializers(Eng, modulePrefix, compatModules);
+
+export default Eng;
+```
 
 ## Lazy Engines
-For lazy engines add devDependency on [`@embroider/router`](https://github.com/embroider-build/embroider/blob/main/packages/router/) which is a drop-in replacement for `@ember/routing/router`:
+
+With the new Embroider+Vite build system you are required to use [`@embroider/router`](https://github.com/embroider-build/embroider/blob/main/packages/router/) as a replacement for your regular Ember Router if you want to maintain the behaviour of your Lazy Engines. All bundle splitting is handled by Embroider and the `@embroider/router` controls loading bundles as you navigate between routes that may have been split by the build, or a lazy engine that may be mounted on a particular route.
+
+The `@embroider/router` is the default for new applications but if you are upgrading an existing app you will need to update your router to use the new drop-in replacement:
 
 ```diff
 // <your app>/app/router.js
 -import EmberRouter from '@ember/routing/router';
 +import EmberRouter from '@embroider/router';
-```
+```
+
+## Legacy Embroider
+
+Before Embroider+Vite became the default for newly generated applications, there was a previous Embroider version that used a mixture of a classic build (with AMD) and Webpack. This version of Embroider is no longer being actively maintained so anyone still using it should actively try to upgrade to Embroider+Vite.
+
+Since `ember-engines` is providing an automatic polyfill that supports classic builds, that same polyfill allows Engines that have been updated to work with Vite to work with the legacy Emberoider@3 build system that relies on Webpack.

tests/dummy/app/templates/docs/migrations.md

@@ -3,6 +3,7 @@
 ### v0.12 -> v0.13
 
 1. Update engine.js to gain vite support for engines
+
     ```diff
     // addon/engine.js
     import Engine from 'ember-engines/engine';
@@ -27,7 +28,7 @@
 
     this change is compatible with classic apps that have not upgraded to vite as long as they also upgrade to `ember-engines@^0.13.0`
 
-1. Only on classic apps (any app that does not use `@embroider/core` in `package.json`)  
+2. Only on classic apps (not being built with Vite - the default for new apps since 6.8)
     Add `ember-asset-loader` as a dev dependency