ci: add actionlint for GitHub Actions workflow linting

Add actionlint integration to lint GitHub Actions workflows:
- Create actionlint.yml workflow to run on push/PR to main
- Add actionlint pre-commit hook using v1.7.9
- Update SessionStart.sh to install actionlint in remote environments
- Add actionlint binary to .gitignore

Author: claude

.claude/hooks/SessionStart.sh

@@ -65,6 +65,16 @@ fi
 
 composer install
 
+# Install actionlint for GitHub Actions workflow linting
+echo "Checking for actionlint..."
+if ! command -v actionlint &> /dev/null && [ ! -f "./actionlint" ]; then
+    echo "actionlint is not installed. Downloading actionlint..."
+    bash <(curl https://raw.githubusercontent.com/rhysd/actionlint/main/scripts/download-actionlint.bash)
+    echo "actionlint installed successfully!"
+else
+    echo "actionlint is already available."
+fi
+
 # Install infection for mutation testing
 echo "Checking for infection..."
 if [ ! -f "infection.phar" ]; then

.github/workflows/actionlint.yml

@@ -0,0 +1,23 @@
+name: Lint GitHub Actions workflows
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  actionlint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Download actionlint
+        id: get_actionlint
+        run: bash <(curl https://raw.githubusercontent.com/rhysd/actionlint/main/scripts/download-actionlint.bash)
+        shell: bash
+      - name: Check workflow files
+        run: ${{ steps.get_actionlint.outputs.executable }} -color
+        shell: bash

.gitignore

@@ -14,3 +14,4 @@ infection.phar.asc
 *.har
 infection*.txt
 infection-report.html
+actionlint

.pre-commit-config.yaml

@@ -8,6 +8,10 @@ repos:
       - id: check-added-large-files
       - id: check-merge-conflict
       - id: detect-private-key
+  - repo: https://github.com/rhysd/actionlint
+    rev: v1.7.9
+    hooks:
+      - id: actionlint
   - repo: https://github.com/compilerla/conventional-pre-commit
     rev: v3.0.0
     hooks: