[Docs] Remove legacy mobx example (#40304)

## Info

This PR merges with-mobx-lite into with-mobx. After that we will migrate `with-mobx` to typescript.

## Context

As discussed in #40302 (comment) we are going to merge the mobx examples.

#40302

## Documentation / Examples

- [x] Make sure the linting passes by running `pnpm lint`
- [x] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)

examples/with-mobx-react-lite/README.md

@@ -1,41 +1,3 @@
-# MobX V6 with Mobx React Lite
+# MobX React Light
 
-Usually splitting your app state into `pages` feels natural but sometimes you'll want to have global state for your app. This is an example on how you can use mobx that also works with our universal rendering approach.
-
-In this example we are going to display a digital clock that updates every second. The first render is happening in the server and then the browser will take over. To illustrate this, the server rendered clock will have a different background color than the client one.
-
-To illustrate SSG and SSR, go to `/ssg` and `/ssr`, those pages are using Next.js data fetching methods to get the date in the server and return it as props to the page, and then the browser will hydrate the store and continue updating the date.
-
-The trick here for supporting universal mobx is to separate the cases for the client and the server. When we are on the server we want to create a new store every time, otherwise different users data will be mixed up. If we are in the client we want to use always the same store. That's what we accomplish on `store.js`.
-
-Page.js component is using the clock store to start and stop the store clock.
-
-Clock.js component is using the clock store to read the time.
-
-StoreProvider.js component is used to instantiate the `Store` both on the server and on the client.
-
-Both components are using a custom hook `useStore` to pull in the `Store` from the provider.
-
-## Deploy your own
-
-Deploy the example using [Vercel](https://vercel.com?utm_source=github&utm_medium=readme&utm_campaign=next-example) or preview live with [StackBlitz](https://stackblitz.com/github/vercel/next.js/tree/canary/examples/with-mobx-react-lite)
-
-[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/git/external?repository-url=https://github.com/vercel/next.js/tree/canary/examples/with-mobx-react-lite&project-name=with-mobx-react-lite&repository-name=with-mobx-react-lite)
-
-## How to use
-
-Execute [`create-next-app`](https://github.com/vercel/next.js/tree/canary/packages/create-next-app) with [npm](https://docs.npmjs.com/cli/init), [Yarn](https://yarnpkg.com/lang/en/docs/cli/create/), or [pnpm](https://pnpm.io) to bootstrap the example:
-
-```bash
-npx create-next-app --example with-mobx-react-lite with-mobx-react-lite-app
-```
-
-```bash
-yarn create next-app --example with-mobx-react-lite with-mobx-react-lite-app
-```
-
-```bash
-pnpm create next-app --example with-mobx-react-lite with-mobx-react-lite-app
-```
-
-Deploy it to the cloud with [Vercel](https://vercel.com/new?utm_source=github&utm_medium=readme&utm_campaign=next-example) ([Documentation](https://nextjs.org/docs/deployment)).
+**Note:** This example has been moved to [examples/with-mobx](../with-mobx/)

examples/with-mobx/README.md

@@ -1,4 +1,4 @@
-# MobX example
+# MobX V6 with Mobx React Lite
 
 Usually splitting your app state into `pages` feels natural but sometimes you'll want to have global state for your app. This is an example on how you can use mobx that also works with our universal rendering approach.
 
@@ -8,28 +8,34 @@ To illustrate SSG and SSR, go to `/ssg` and `/ssr`, those pages are using Next.j
 
 The trick here for supporting universal mobx is to separate the cases for the client and the server. When we are on the server we want to create a new store every time, otherwise different users data will be mixed up. If we are in the client we want to use always the same store. That's what we accomplish on `store.js`.
 
-The clock, under `components/Clock.js`, has access to the state using the `inject` and `observer` functions from `mobx-react`. In this case Clock is a direct child from the page but it could be deep down the render tree.
+Page.js component is using the clock store to start and stop the store clock.
+
+Clock.js component is using the clock store to read the time.
+
+StoreProvider.js component is used to instantiate the `Store` both on the server and on the client.
+
+Both components are using a custom hook `useStore` to pull in the `Store` from the provider.
 
 ## Deploy your own
 
-Deploy the example using [Vercel](https://vercel.com?utm_source=github&utm_medium=readme&utm_campaign=next-example) or preview live with [StackBlitz](https://stackblitz.com/github/vercel/next.js/tree/canary/examples/with-mobx)
+Deploy the example using [Vercel](https://vercel.com?utm_source=github&utm_medium=readme&utm_campaign=next-example) or preview live with [StackBlitz](https://stackblitz.com/github/vercel/next.js/tree/canary/examples/with-mobx-react-lite)
 
-[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/git/external?repository-url=https://github.com/vercel/next.js/tree/canary/examples/with-mobx&project-name=with-mobx&repository-name=with-mobx)
+[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/git/external?repository-url=https://github.com/vercel/next.js/tree/canary/examples/with-mobx-react-lite&project-name=with-mobx-react-lite&repository-name=with-mobx-react-lite)
 
 ## How to use
 
 Execute [`create-next-app`](https://github.com/vercel/next.js/tree/canary/packages/create-next-app) with [npm](https://docs.npmjs.com/cli/init), [Yarn](https://yarnpkg.com/lang/en/docs/cli/create/), or [pnpm](https://pnpm.io) to bootstrap the example:
 
 ```bash
-npx create-next-app --example with-mobx with-mobx-app
+npx create-next-app --example with-mobx-react-lite with-mobx-react-lite-app
 ```
 
 ```bash
-yarn create next-app --example with-mobx with-mobx-app
+yarn create next-app --example with-mobx-react-lite with-mobx-react-lite-app
 ```
 
 ```bash
-pnpm create next-app --example with-mobx with-mobx-app
+pnpm create next-app --example with-mobx-react-lite with-mobx-react-lite-app
 ```
 
 Deploy it to the cloud with [Vercel](https://vercel.com/new?utm_source=github&utm_medium=readme&utm_campaign=next-example) ([Documentation](https://nextjs.org/docs/deployment)).

examples/with-mobx/components/Clock.js

@@ -1,8 +1,13 @@
-import { observer } from 'mobx-react'
-const Clock = observer((props) => {
+import { observer } from 'mobx-react-lite'
+import { useStore } from './StoreProvider'
+
+const Clock = observer(function Clock(props) {
+  // use store from the store context
+  const store = useStore()
+
   return (
-    <div className={props.light ? 'light' : ''}>
-      {props.timeString}
+    <div className={store.light ? 'light' : ''}>
+      {store.timeString}
       <style jsx>{`
         div {
           padding: 15px;
@@ -19,4 +24,5 @@ const Clock = observer((props) => {
     </div>
   )
 })
+
 export default Clock