feat: add workflow to publish templates to ghcr.io

Templates will be available in VS Code via:
F1 → Dev Containers: Add Dev Container Configuration Files...

Author: Pikatsuto

.github/workflows/publish-templates.yml

@@ -0,0 +1,56 @@
+name: Publish Dev Container Templates
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - '.devcontainer/**/devcontainer-template.json'
+      - '.github/workflows/publish-templates.yml'
+  workflow_dispatch:
+
+env:
+  REGISTRY: ghcr.io
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+
+      - name: Install devcontainer CLI
+        run: npm install -g @devcontainers/cli
+
+      - name: Log in to Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Publish templates
+        run: |
+          OWNER="${{ github.repository_owner }}"
+          OWNER_LC=$(echo "$OWNER" | tr '[:upper:]' '[:lower:]')
+
+          # Find and publish all templates
+          for template_dir in .devcontainer/*/; do
+            if [[ -f "${template_dir}devcontainer-template.json" ]]; then
+              template_name=$(basename "$template_dir")
+              echo "Publishing template: $template_name"
+
+              devcontainer templates publish "$template_dir" \
+                --registry "${{ env.REGISTRY }}" \
+                --namespace "$OWNER_LC"
+            fi
+          done

README.md

@@ -20,7 +20,15 @@ Dev Container templates with Claude Code pre-installed on Debian 13 (Trixie).
 
 ## Usage
 
-### Option 1: Copy the devcontainer folder
+### Option 1: Use from VS Code (recommended)
+
+1. Open any folder in VS Code
+2. Press `F1` → "Dev Containers: Add Dev Container Configuration Files..."
+3. Select "Show All Definitions..."
+4. Search for `ghcr.io/pikatsuto/claude-code`
+5. Choose your template (base or base-with-bmad)
+
+### Option 2: Copy the devcontainer folder
 
 Copy the desired template folder from `.devcontainer/` to your project:
 
@@ -32,7 +40,7 @@ cp -r .devcontainer/base /your-project/.devcontainer
 cp -r .devcontainer/base-with-bmad /your-project/.devcontainer
 ```
 
-### Option 2: Use the image directly
+### Option 3: Use the image directly
 
 Create a `.devcontainer/devcontainer.json` in your project:
 
@@ -48,7 +56,7 @@ Create a `.devcontainer/devcontainer.json` in your project:
 }
 ```
 
-### Option 3: Extend the image
+### Option 4: Extend the image
 
 Create your own Dockerfile based on this image:
 
@@ -104,7 +112,8 @@ echo $GITHUB_TOKEN | docker login ghcr.io -u USERNAME --password-stdin
 │       └── devcontainer-template.json
 ├── .github/
 │   └── workflows/
-│       └── build-container.yml
+│       ├── build-container.yml
+│       └── publish-templates.yml
 ├── devcontainer-collection.json
 └── README.md
 ```