Fix: Add GitHub Actions workflow for automated publishing

.github/workflows/publish.yml

@@ -0,0 +1,43 @@
+name: Publish VS Code Extension
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v4
+      
+    - name: Setup Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '18'
+        cache: 'npm'
+        
+    - name: Install dependencies
+      run: npm ci
+      
+    - name: Update version from release tag
+      run: |
+        VERSION=${GITHUB_REF#refs/tags/v}
+        npm version $VERSION --no-git-tag-version
+        
+    - name: Package extension
+      run: npm run vscode:prepublish
+      
+    - name: Publish to marketplace
+      run: npx @vscode/vsce publish --pat ${{ secrets.VSCE_PAT }}
+      
+    - name: Upload VSIX as release asset
+      uses: actions/upload-release-asset@v1
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      with:
+        upload_url: ${{ github.event.release.upload_url }}
+        asset_path: ./humanagent-mcp-${{ github.event.release.tag_name }}.vsix
+        asset_name: humanagent-mcp-${{ github.event.release.tag_name }}.vsix
+        asset_content_type: application/zip