fix(ci): update all workflows to use Node.js 20

Update Node.js version from 18 to 20 in all GitHub Actions workflows
to meet dependency requirements. This fixes CI failures caused by
packages requiring Node.js 20+.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.github/workflows/auto-release.yml

@@ -30,7 +30,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: '18'
+          node-version: '20'
           cache: 'npm'
 
       - name: Configure Git

.github/workflows/check.yml

@@ -24,7 +24,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: '18'
+          node-version: '20'
           cache: 'npm'
 
       - name: Install dependencies
@@ -44,7 +44,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: '18'
+          node-version: '20'
           cache: 'npm'
 
       - name: Install dependencies
@@ -68,7 +68,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: '18'
+          node-version: '20'
           cache: 'npm'
 
       - name: Install dependencies

.github/workflows/release.yml

@@ -15,7 +15,7 @@ jobs:
       - name: Use Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: "18"
+          node-version: "20"
 
       - name: Build plugin
         run: |

.github/workflows/semantic-release.yml

@@ -26,7 +26,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: '18'
+          node-version: '20'
           cache: 'npm'
 
       - name: Install dependencies