Remove yarn, use npm exclusively

Replace all yarn references with npm across README, CLAUDE.md,
CHANGELOG, .gitignore, and CI workflow. Remove yarn.lock.

Co-Authored-By: Claude <noreply@anthropic.com>

.gitea/workflows/release.yml

@@ -113,7 +113,6 @@ jobs:
             -x "${THEME_NAME}/src/*" \
             -x "${THEME_NAME}/package.json" \
             -x "${THEME_NAME}/package-lock.json" \
-            -x "${THEME_NAME}/yarn.lock" \
             -x "${THEME_NAME}/composer.json" \
             -x "${THEME_NAME}/composer.lock" \
             -x "${THEME_NAME}/.gitignore" \

.gitignore

@@ -15,8 +15,8 @@ vendor/
 .DS_Store
 Thumbs.db
 
-# Yarn
-yarn-error.log
+# npm
+npm-debug.log
 
 # Backup files
 *.bak

CHANGELOG.md

@@ -27,7 +27,7 @@ All notable changes to this project will be documented in this file.
 ### Added
 
 - Initial theme scaffolding
-- Bootstrap 5 CSS and JS integration (served locally via Yarn)
+- Bootstrap 5 CSS and JS integration (served locally via npm)
 - SASS build pipeline with Dart Sass, PostCSS, Autoprefixer, cssnano
 - Twig 3.0 template engine integration via Composer
 - FSE templates: index, home, single, page, archive, search, 404

CLAUDE.md

@@ -44,7 +44,7 @@ Next milestone is **v0.2.0 - Design Editor**. See `PLAN.md` for details.
 - **Template Engine:** Twig 3.0 (via Composer)
 - **Frontend:** Bootstrap 5 Javascript & Vanilla JavaScript
 - **Styling:** Bootstrap 5 & Custom CSS (if necessary)
-- **Dependency Management:** Composer (PHP), npm/Yarn (JS/CSS)
+- **Dependency Management:** Composer (PHP), npm (JS/CSS)
 - **Internationalization:** WordPress i18n (.pot/.po/.mo files)
 - **Canonical Plugin Name:** `wp-bootstrap`
 
@@ -178,7 +178,7 @@ Build steps (in order):
 3. `scss` — Compile SCSS (`src/scss/`) to CSS (`assets/css/`)
 4. `postcss` — Autoprefixer + cssnano minification → `assets/css/style.min.css`
 
-**CI/CD note:** The Gitea workflow uses `npm install` and `npm run build` (not `yarn`). The CI runner does not have `yarn` available.
+**CI/CD note:** The Gitea workflow uses `npm install` and `npm run build`.
 
 ### Architecture Notes
 
@@ -205,7 +205,7 @@ Build steps (in order):
 
 **Key learnings:**
 
-- `actions/setup-node@v4` does not install `yarn` — use `npm install` / `npm run build` in CI workflows
+- CI uses `npm install` / `npm run build` — `yarn` is not available in the CI runner
 - Bootstrap 5 alert colors are hardcoded (not CSS variables), so explicit dark mode overrides are needed in SCSS
 - Anti-flash for dark mode requires a synchronous inline script via `wp_add_inline_script('handle', '...', 'before')` — the deferred JS alone causes a flash
 - Variable fonts use `fontWeight: "100 900"` range syntax in `theme.json` `fontFace` declarations

README.md

@@ -31,8 +31,8 @@ A modern WordPress Block Theme built from scratch with Bootstrap 5.
 git clone ssh://git@src.bundespruefstelle.ch:2022/magdev/wp-bootstrap.git
 cd wp-bootstrap
 composer install
-yarn install
-yarn build
+npm install
+npm run build
 ```
 
 ## Development
@@ -40,7 +40,7 @@ yarn build
 ### Prerequisites
 
 - Node.js 20+
-- Yarn
+- npm
 - Composer
 - PHP 8.3+
 
@@ -48,10 +48,10 @@ yarn build
 
 | Command | Description |
 | --- | --- |
-| `yarn build` | Compile SCSS, minify CSS, copy Bootstrap JS |
-| `yarn dev` | Watch SCSS files and recompile on changes |
-| `yarn scss` | Compile SCSS only |
-| `yarn postcss` | Minify CSS with Autoprefixer |
+| `npm run build` | Compile SCSS, minify CSS, copy Bootstrap JS |
+| `npm run dev` | Watch SCSS files and recompile on changes |
+| `npm run scss` | Compile SCSS only |
+| `npm run postcss` | Minify CSS with Autoprefixer |
 | `composer install` | Install PHP dependencies |
 
 ### Project Structure