ci: add GitHub Actions workflow for GitHub Pages deployment

- pnpm 10 + Node 22 for fastest CI
- Frozen lockfile, upload-pages-artifact v3, deploy-pages v4
- Vite base path set to /skwik/ when building in GHA
- Concurrency group cancels in-progress deploys

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

.github/workflows/deploy.yml

@@ -0,0 +1,50 @@
+name: Deploy to GitHub Pages
+
+on:
+  push:
+    branches: [main]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: pages
+  cancel-in-progress: true
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: pnpm/action-setup@v4
+        with:
+          version: 10
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: pnpm
+
+      - run: pnpm install --frozen-lockfile
+
+      - run: pnpm build
+        env:
+          NODE_OPTIONS: --max-old-space-size=4096
+
+      - uses: actions/upload-pages-artifact@v3
+        with:
+          path: dist
+
+  deploy:
+    needs: build
+    runs-on: ubuntu-latest
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - id: deployment
+        uses: actions/deploy-pages@v4

vite.config.ts

@@ -4,6 +4,7 @@ import tailwindcss from "@tailwindcss/vite";
 import { resolve } from "node:path";
 
 export default defineConfig({
+  base: process.env.GITHUB_ACTIONS ? "/skwik/" : "/",
   plugins: [vue(), tailwindcss()],
   resolve: {
     alias: {