Add config files, docs, and test placeholders; rename configs

Introduces standard configuration files for linting, formatting, and environment management (.editorconfig, .browserslistrc, .eslintignore, .prettierignore, .npmrc, .nvmrc, etc.), as well as documentation for agents and global rules. Moves and renames config files to use .cjs extensions for ESLint, Jest, Playwright, PostCSS, Stylelint, and Webpack. Adds placeholder E2E and unit test files. Improves project structure and standardisation.

Author: ashleyshaw

.browserslistrc

@@ -0,0 +1,4 @@
+>0.5%
+last 2 versions
+not dead
+extends @wordpress/browserslist-config

.editorconfig

@@ -0,0 +1,52 @@
+# EditorConfig is awesome: https://EditorConfig.org
+root = true
+
+# Unix-style
+newlines with a newline ending every file
+[*]
+charset = utf-8
+end_of_line =
+lf
+insert_final_newline = true
+charset = utf-8
+indent_style = space
+indent_size =
+2
+trim_trailing_whitespace = true
+
+# 4 space indentation for PHP
+files
+[*.php]
+indent_style = tab
+indent_size = 4
+
+# 2 space indentation for JS
+files
+[*.js]
+indent_size = 2
+
+# 2 space indentation for CSS and SCSS
+files
+[*.{css,scss}]
+indent_size = 2
+tab_width = 2
+
+# 2 space indentation for JSON files
+[*.json]
+indent_size =
+2
+indent_style = space
+tab_width = 2
+
+# 2 space indentation for YAML
+files
+[*.{yml,yaml}]
+indent_size = 2
+indent_style = space
+tab_width = 2
+
+# Markdown
+files
+[*.md]
+max_line_length = off
+trim_trailing_whitespace = false

eslint.config.js .eslint.config.cjseslint.config.js renamed to .eslint.config.cjs

@@ -36,4 +36,4 @@ module.exports = {
 			},
 		},
 	],
-};
+};

.eslintignore

@@ -0,0 +1,20 @@
+# Ignore files and directories that should not be formatted by Eslint
+
+# Node
+modules
+node_modules
+
+# Build directories
+build
+dist
+
+# Log files
+
+# Vendor
+directories
+vendor
+
+# Test directories
+coverage
+playwright-report
+test-results

.gitattributes

@@ -0,0 +1,54 @@
+/.github 				export-ignore
+/.idea/               	export-ignore
+/.npm/
+     	export-ignore
+/.sass-cache/         	export-ignore
+/.vscode/
+	export-ignore
+/docs/                	export-ignore
+/tests/
+	export-ignore
+/vendor/               	export-ignore
+/node_modules/
+	export-ignore
+/.gitattributes 		export-ignore
+/.gitignore 			export-ignore
+/.editorconfig
+       	export-ignore
+/cli.php               	export-ignore
+/*.md
+   	export-ignore
+/phpcs.xml.dist       	export-ignore
+/phpunit.xml.dist
+	export-ignore
+/LICENSE.md           	-export-ignore
+/README.md
+	-export-ignore
+/composer.json        	export-ignore
+/composer.lock
+	export-ignore
+/package.json         	export-ignore
+/package-lock.json
+	export-ignore
+/yarn.lock            	export-ignore
+/.styleci.yml
+	export-ignore
+/.travis.yml          	export-ignore
+/.scrutinizer.yml
+	export-ignore
+/.codeclimate.yml     	export-ignore
+/.php_cs.dist
+	export-ignore
+/.php-cs-fixer.dist.php export-ignore
+/.htaccess            	export-ignore
+/web.config
+	export-ignore
+/.phpstorm.meta.php   	export-ignore
+/.DS_Store
+	export-ignore
+/.env.example         	export-ignore
+*.zip 					export-ignore
+* text=auto
+eol=lf
+*.lock text
+*.bat text eol=crlf

.github/agents/agent.md

@@ -0,0 +1,19 @@
+# Single Block WP Plugin — Primary Agent
+
+- **Agent:**
+`wp-block-build-agent.js`
+- **Workflow:** `.github/workflows/block-build-and-e2e.yml`
+- **Purpose:**
+Automate a common, repeatable quality task for this repository type.
+- **Usage:**
+
+- GitHub Actions: see the workflow file for triggers and env.
+  - Local: `node
+.github/agents/wp-block-build-agent.js`
+- **Environment variables:**
+  -
+`DRY_RUN` (default: `false`), `VERBOSE` (default: `false`)
+  - Additional secrets per
+workflow (e.g. `GITHUB_TOKEN` for label ops).
+- **Maintenance:** Keep the agent
+aligned with repo tooling (linters, build, tests).