Migrate to NX-based build (#151)

## Description

Sets up the correct build pipeline for all parts of Playground and PHP.wasm. This enables a public release of the [Playground API](#149) npm package!

I've been [struggling](#146) with [this](#70) for [a while](#150) and couldn't understand what's so hard. NX made it apparent – look at this dependency graph!

<img width="1291" alt="CleanShot 2023-03-16 at 23 16 26@2x" src="https://user-images.githubusercontent.com/205419/225764795-7fa8e972-09f8-41ef-aac2-1c96bd100ea0.png">

No wonder it's been almost impossible to set everything up by hand!

## Usage

Start with `yarn install`

### Shortcuts

To start a copy of `wasm.wordpress.net` locally, run `yarn run dev`.
To build it, run `yarn run build`.

### Fully qualified commands

In reality, these `yarn run` commands are just triggering the underlying project's nx `dev` and `build` commands:

```bash
nx dev playground-website
nx build playground-website
```

Here's a few more interesting commands:

```bash
# Build and run PHP.wasm CLI
nx start php-wasm-cli

# Build latest WordPress releases
nx recompile-wordpress:all playground-remote

# Recompile PHP 5.6 - 8.2 releases to .wasm for web
nx recompile-php:all php-wasm-web

# Recompile PHP 5.6 - 8.2 releases to .wasm for node
nx recompile-php:all php-wasm-node

# Builds markdown files for readthedocs site
nx build docs-site

# Builds the Playground Client npm package
nx build playground-client
```

## NX is the tool Playground needed from the outset

It's ridiculous how many problems this solves:

* The build pipeline is explicitly defined and easy to modify
* Tasks only run once their dependencies are ready
* The dev mode works and is fast
* The build works and is fast
* We get CI checks to confirm the entire build process still works (which solves #150)
* Cross-package TypeScript just works
* There are linters and formatters (which solves #14)
* Documentation is correctly generated from the latest built artifacts
* There are nice generators for bootstraping new packages and moving the existing ones around
* There are checks to ensure the private `php-wasm-common` package is not imported by anything else than `php-wasm-web` and `php-wasm-node`

## Next steps

* Add Lerna to harness package publishing
* Additional developer documentation for the nx-based flow

Related to #148 and #147

.editorconfig

@@ -0,0 +1,13 @@
+# Editor configuration, see http://editorconfig.org
+root = true
+
+[*]
+charset = utf-8
+indent_style = space
+indent_size = 2
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.md]
+max_line_length = off
+trim_trailing_whitespace = false

.eslintignore

@@ -1,4 +1,10 @@
-node_modules/**/*
-build/*
-packages/*/build*/*
-src/php-wasm/wasm/build-assets/*
+node_modules
+packages/php-wasm/node/public
+packages/php-wasm/web/public
+packages/php-wasm/compile/build-assets
+packages/playground/compile-wordpress/build-assets
+__pycache__
+packages/playground/remote/src/wordpress
+*.timestamp-1678999213403.mjs
+.local
+.vscode

.eslintrc.json

@@ -0,0 +1,51 @@
+{
+	"root": true,
+	"ignorePatterns": ["**/*"],
+	"plugins": ["@nrwl/nx"],
+	"overrides": [
+		{
+			"files": ["*.ts", "*.tsx", "*.js", "*.jsx"],
+			"rules": {
+				"@nrwl/nx/enforce-module-boundaries": [
+					"error",
+					{
+						"enforceBuildableLibDependency": true,
+						"allow": [],
+						"depConstraints": []
+					}
+				],
+				"no-inner-declarations": 0,
+				"no-use-before-define": "off",
+				"react/prop-types": 0,
+				"no-console": 0,
+				"no-empty": 0,
+				"no-async-promise-executor": 0,
+				"no-constant-condition": 0,
+				"no-nested-ternary": 0,
+				"jsx-a11y/click-events-have-key-events": 0,
+				"jsx-a11y/no-static-element-interactions": 0
+			}
+		},
+		{
+			"files": ["*.ts", "*.tsx"],
+			"extends": ["plugin:@nrwl/nx/typescript"],
+			"rules": {
+				"@typescript-eslint/ban-ts-comment": 0,
+				"@typescript-eslint/ban-types": 0,
+				"@typescript-eslint/no-non-null-assertion": 0,
+				"@typescript-eslint/no-explicit-any": 0,
+				"no-constant-condition": 0
+			}
+		},
+		{
+			"files": ["*.js", "*.jsx"],
+			"extends": ["plugin:@nrwl/nx/javascript"],
+			"rules": {}
+		},
+		{
+			"files": "*.json",
+			"parser": "jsonc-eslint-parser",
+			"rules": {}
+		}
+	]
+}

.github/workflows/ci.yml

@@ -0,0 +1,25 @@
+name: CI
+on:
+    push:
+        branches:
+            - trunk
+    pull_request:
+
+jobs:
+    main:
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/checkout@v2
+              with:
+                  fetch-depth: 0
+            - uses: nrwl/nx-set-shas@v3
+              with:
+                  main-branch-name: 'trunk'
+            - run: npm install -g yarn nx
+            - run: yarn install --frozen-lockfile
+
+            - run: nx format:check
+            - run: nx affected --target=lint --parallel=3
+            # No test setup yet
+            # - run: nx affected --target=test --parallel=3 --configuration=ci
+            - run: nx affected --target=build --parallel=3

.gitignore

@@ -1,32 +1,48 @@
-.DS_Store
-.idea
-.local
+# See http://help.github.com/ignore-files/ for more about ignoring files.
+
+# compiled output
+dist
+tmp
+var
+/out-tsc
 .vitepress
-.vite
-.pnp.*
-.yarn/*
-!.yarn/patches
-!.yarn/plugins
-!.yarn/releases
-!.yarn/sdks
-!.yarn/versions
-.rollup.cache
+__pycache__
+
+# dependencies
 node_modules
-/live-code-example
-/testwp
-package-lock.json
-packages/*/build
-testwp
-!build/wp-admin
-!build/wp-content
-!build/wp-includes
-!build/php.wasm
-!build/php.js
-!build/wp.data
-!build/wp.js
-*.tsbuildinfo
-*.d.ts
-tsdoc-metadata.json
-var
-dist.zip
+
+# IDEs and editors
+/.idea
+/.local
 .vscode
+.project
+.classpath
+.c9/
+*.launch
+.settings/
+*.sublime-workspace
+
+# IDE - VSCode
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+
+# misc
+/.sass-cache
+/connect.lock
+/coverage
+/libpeerconnection.log
+npm-debug.log
+yarn-error.log
+testem.log
+/typings
+*.timestamp-1678999213403.mjs
+
+# System Files
+.DS_Store
+Thumbs.db
+
+# Playground artifacts
+php.js.bak

.nxignore

@@ -0,0 +1,11 @@
+node_modules
+dist
+packages/php-wasm/node/public
+packages/php-wasm/web/public
+packages/php-wasm/compile/build-assets
+packages/playground/compile-wordpress/build-assets
+__pycache__
+packages/playground/remote/src/wordpress
+*.timestamp-1678999213403.mjs
+.local
+.vscode

.prettierignore

@@ -1,3 +1,13 @@
-node_modules/**/*
-build/*
-packages/*/build*/*
+# Add files here to ignore them from prettier formatting
+/dist
+/coverage
+/node_modules
+/packages/php-wasm/node/public
+/packages/php-wasm/web/public
+/packages/php-wasm/compile/build-assets
+/packages/playground/compile-wordpress/build-assets
+/packages/playground/remote/src/wordpress
+__pycache__
+*.timestamp-1678999213403.mjs
+.local
+.vscode

.prettierrc

@@ -0,0 +1,7 @@
+{
+  "trailingComma": "es5",
+  "tabWidth": 4,
+  "useTabs": true,
+  "semi": true,
+  "singleQuote": true
+}

.readthedocs.yaml

@@ -12,10 +12,9 @@ version: 2
 #     python: "3.10"
 
 mkdocs:
-  configuration: mkdocs.yml
+    configuration: mkdocs.yml
 
 # Optionally declare the Python requirements required to build your docs
 python:
-   install:
-   - requirements: docs/requirements.txt
-
+    install:
+        - requirements: docs/requirements.txt

README.md

@@ -1,6 +1,6 @@
 # WordPress Playground
 
-[Project Page](https://developer.wordpress.org/playground/) | [Live demo](https://wasm.wordpress.net/wordpress.html) | [Documentation and API Reference](https://wordpresswasm.readthedocs.io/en/latest/) 
+[Project Page](https://developer.wordpress.org/playground/) | [Live demo](https://wasm.wordpress.net/wordpress.html) | [Documentation and API Reference](https://wordpresswasm.readthedocs.io/en/latest/)
 
 [WordPress Playground](https://github.com/WordPress/wordpress-playground) is an experimental in-browser WordPress that runs without a PHP server thanks to the magic of WebAssembly.
 
@@ -34,8 +34,6 @@ npm install -g yarn
 git clone https://github.com/WordPress/wordpress-playground
 cd wordpress-playground
 yarn install
-# An initial build is needed at the moment:
-yarn run build
 yarn run dev
 ```