Add GitHub Actions workflow for VS Code extension build

Introduces a build workflow using GitHub Actions to automate building the VS Code extension on push to main and on manual dispatch. Also updates package.json to use 'markdownDescription' instead of 'description' for a configuration property.

Author: Mqxx

.github/workflows/build.yml

@@ -0,0 +1,33 @@
+name: Build VS Code Extension
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build extension
+        run: npm run build
+
+      - name: Upload VSIX artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: vs-code-extension
+          path: "*.vsix"

package.json

@@ -30,7 +30,7 @@
         "newPackage.fileName": {
           "type": "string",
           "default": "index.ts",
-          "description": "File name for the main file created in the new package folder."
+          "markdownDescription": "File name for the main file created in the new package folder."
         }
       }
     },