- Making font optimizations as default
- Re-enabling tests
- Fixes #19159

This PR removes the `next.config.js` file with an `env` key and instead modifies the setup script to create a `.env.local` file with the provided credentials. 

I also made some changes to the Deploy Button to ask for the environment variables when creating a new project. 

## Problems with the other implementation
- pixel not working first time load page (this generate fake information to facebook analytics data)
- package react-facebook-pixel  error when try use events in code blocks or other pages with the current implementation
- sometimes pixel mark twice pageview (this generate warning in facebook panel)
- standar or custom events not working

## Solutions
- Initialize pixel when entering each page (_document)
- Now, we can use custom and standar events (utils/fpixel.js)
- correct way to implement pixel according to facebook and guide facebook to implement in SPA
- this solution is complemented with example "with-google-analytics"

In my opinion, the other development has problems, but I preferred created a new example because the way to implement the base code is different. It seems that the other example is based on set the events from the Facebook control panel then this method limits an advanced implementation.

The example stopped working when the GraphQL service [Graphcool](https://www.graph.cool/) shut down in July. I have replaced it with an [Hasura](https://hasura.io/) endpoint.

Fixes #19093 

Remove extra word "the"

We've received some feedback that the current note about calling API routes inside gSP/gSSP is confusing. This updates the wording to make it clear you can still use `fetch` in your application, and also to not say you "import" an API route. You import the _logic_ inside the route.

This updates to the latest version of the `@ampproject/toolbox-optimizer` which contains updates for dependencies to remove the warnings on install from `npm`

x-ref: https://github.com/vercel/next.js/pull/18994
Closes: https://github.com/vercel/next.js/issues/17416

* make the error message more clear if webpack config comes back undefined

* Update check and add test

* bump

* Update build-output test
Co-authored-by: NJJ Kasper <jj@jjsweb.site>

Co-authored-by: NJJ Kasper <jj@jjsweb.site>

dotenv currently doesn't support inline comments (see https://github.com/motdotla/dotenv/issues/484), so it's misleading to use inline comments in documentation examples.

Build directory is `dist` and not `build`. The typo also makes gitignore not work correctly.

Updated one of the deployment steps to make sure the deployment of the home app is not done without pushing the blog URL first!

The [default loader](https://github.com/vercel/next.js/blob/17b91e7c76711308707bc8ab3308376af98170e6/packages/next/client/image.tsx#L488) and [imgix loader](https://docs.imgix.com/apis/rendering/format/q) use a quality of 75 if none is specified on the Image component.

This PR does something similar for the cloudinary loader by utilizing `q_auto`, but it should yield even better results.

> This setting can significantly reduce the file size without any degradation noticeable to the human eye, and without the need for you to individually analyze every image.

https://cloudinary.com/documentation/image_optimization#use_q_auto_automatic_quality_and_encoding

### Example
- [Before](https://res.cloudinary.com/demo/image/upload/woman.jpg) - 583KB
- [After](https://res.cloudinary.com/demo/image/upload/q_auto/woman.jpg) - 46KB

This PR closes #19649.

Either use `avoid` or `prevent` as verb, but not both.

Fixes https://github.com/vercel/next.js/issues/19571

This reverts #18921 and ensures that the Babel runtime is only inlined as an absolute path when using PnP as before, but then including the correction this resolution as implemented by @merceyz only in the PnP cases, while keeping the diff to a minimum.

This breaks up the `serverless-loader` into typed handlers to allow for easier maintenance and better type-checking/linting. 

Closes: https://github.com/vercel/next.js/issues/19071

Hello, this PR updates the with-tailwindcss-emotion example to be compatible with tailwindcss 2.0

Here is a summary of all the changes:
- update `.babelrc` config
- update `README.md`
- delete `@emotion/css component` (makes the example simpler)
- update `@emotion/react` component to use xwind
- update `@emotion/styled` component to use xwind
- Add global styles to `_app.js`
- remove `_document.js` page
- remove `base.css` global style files (global styles are added in _app.js)
- update `tailwind.config.js`
- update `package.json` dependencies + remove unnecessary `build:base-css` script

By default, MobX 6 and later require that you use `actions` to make changes to the state, otherwise, it issues a warning in the console, because the `hydrate` method of the `store.js` class hasn't been declared an action, you can see this warning if you try to load pages that use hydration (ssg, ssr).
This pull request fixes that.

More info about the behavior:
https://mobx.js.org/actions.html#disabling-mandatory-actions-

Fixes #16173

## What

Restores handling of termination signals, `SIGTERM` and `SIGINT`, to allow graceful termination of next commands. Seems to have been removed during a child process refactor #6450, was this intentional?

## Why 

Currently the command processes have to be forcefully killed. This would help those using Next.js with custom servers and tools like Docker and Kubernetes that rely on termination signals to shutdown instances.

---

Where would be a good location to add some tests? [test/integration/cli/test/index.test.js](https://github.com/vercel/next.js/blob/fc98c13a2e6bc545073de0eedbe045352b387f6d/test/integration/cli/test/index.test.js)?

To clarify what I've noticed as a common source of confusion in discussions online. Fixes https://github.com/vercel/next.js/issues/19426 

If you wish to know whether the code is running as part of a client-side page transition, in either `getInitialProps` or `getServerSideProps`, you can check to see if `context.req.url` starts with `/_next/data`.

Fixes https://github.com/vercel/next.js/issues/19503

- Updated some links in docs that don't have the `.md` extension. Not required for our live docs but useful for the GitHub view.
- Updated links that go to https://nextjs.org/docs to a relative path, that way they'll work for versioned docs
- Updated the `Regex Path Matching` example to be consistent with the paragraph above and with the official example in /examples.

The code here should contain a regex path matching example, as stated in the comment; but it is the same as the wildcard path matching example above.

https://nextjs.org/docs/api-reference/next.config.js/redirects#regex-path-matching

For an API route to work, you need to `export as default a function` (a.k.a **request handler**), which then receives the following parameters:
For an API route to work, you need to `export a function as default` (a.k.a **request handler**), which then receives the following parameters:


I might be wrong though (not a native English speaker), it just sounds strange to my ears.

I couldn't find an example when creating an SSR page using firebase's firestore data, so I improved the example based on the actual app I created

My sample app: https://github.com/mikan3rd/commitly

Fixes https://github.com/vercel/next.js/issues/19486

Adding a example with **Neo4j** native graph database.

- with-neo4j: basic api routes with neo4j driver.

:)

Leverage [execa](https://github.com/sindresorhus/execa) for writing to `stdin`.