ci: build VitePress for CI + Netlify; sync package-lock

The Netlify deploy preview and the GitHub Actions "build" job both failed:

- `npm ci` errored because package-lock.json was out of sync with the
  VitePress dependency tree (terser, acorn, axios, …). Regenerated the
  lock so `npm ci` installs cleanly.
- The build pipeline still targeted VuePress (`npm run build` →
  `vuepress build`, publishing docs/.vuepress/dist), which now fails on
  the ported content. Point CI at `npm run build:vitepress` and publish
  docs/.vitepress/dist, and add a netlify.toml so deploy previews build
  the VitePress site (overriding the stale UI build settings).

Verified locally with Node 22: `npm ci` + `npm run build:vitepress` both
succeed and emit docs/.vitepress/dist.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: ConorOkus

.github/workflows/build.yml

@@ -26,13 +26,13 @@ jobs:
       - name: Install
         run: npm ci
       - name: Build
-        run: npm run build
+        run: npm run build:vitepress
       # Deploy, limited to the main branch
       - name: Deploy
         if: success() && github.ref == 'refs/heads/main'
         uses: peaceiris/actions-gh-pages@v4
         with:
-          publish_dir: ./docs/.vuepress/dist
+          publish_dir: ./docs/.vitepress/dist
           github_token: ${{ secrets.GITHUB_TOKEN }}
           cname: lightningdevkit.org
           user_name: 'github-actions[bot]'

netlify.toml

@@ -0,0 +1,9 @@
+# Build the VitePress site for Netlify deploy previews (and production).
+# Overrides any build command/publish dir configured in the Netlify UI,
+# which still pointed at the old VuePress pipeline.
+[build]
+  command = "npm run build:vitepress"
+  publish = "docs/.vitepress/dist"
+
+[build.environment]
+  NODE_VERSION = "22"