feat(website): add SEO, sitemap, redirects, CI workflow, and Vercel config (#10156)

## Summary

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## Changes

- **What**: <!-- Core functionality added/modified -->
- **Breaking**: <!-- Any breaking changes (if none, remove this line)
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- **Dependencies**: <!-- New dependencies (if none, remove this line)
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## Review Focus

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## Screenshots (if applicable)

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┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10156-feat-website-add-SEO-sitemap-redirects-CI-workflow-and-Vercel-config-3266d73d3650816ab9eaebd11072d481)
by [Unito](https://www.unito.io)

---------

Co-authored-by: GitHub Action <action@github.com>

apps/website/package.json

@@ -9,6 +9,7 @@
     "preview": "astro preview"
   },
   "dependencies": {
+    "@astrojs/sitemap": "catalog:",
     "@comfyorg/design-system": "workspace:*",
     "@vercel/analytics": "catalog:",
     "vue": "catalog:"