feat: Web app version hosted on Vercel

[dernerl]

Problem Description

ManagedFavsGenerator is currently macOS-only. IT admins on Windows or Linux have no access to the tool, and there is no way to share or use it without installing a native app.

Proposed Solution

Build a web app version of ManagedFavsGenerator using React + TypeScript, hosted on Vercel as a static site — no backend required, everything runs in the browser.

Why Vercel over GitHub Pages / Netlify

	GitHub Pages	Netlify	Vercel
Auto-deploy on push	Manual/Actions	✅	✅
PR Preview deployments	❌	✅	✅
React/Vite zero-config	❌	✅	✅
GitHub integration	Native	Good	Good
Free tier	✅	✅	✅

Vercel is the natural fit for a React app and PR preview deployments are especially valuable for open source contributions — every pull request gets a live preview URL automatically.

Architecture

• React + TypeScript (static, no backend)
• Port core logic from Swift to TypeScript:
  • FormatGenerator → JSON & Plist output
  • FormatParser → JSON & Plist import
  • FavoritesViewModel → React state
• Browser APIs replace native services (Clipboard API, file download/upload, localStorage)
• Favicon loading via existing Google/DuckDuckGo providers

Suggested Phases

Phase 1 — Core Logic
Port FormatGenerator and FormatParser to TypeScript including unit tests

Phase 2 — UI
Rebuild the favorites list, folder management, and output panels in React (with drag & drop)

Phase 3 — Features
Import JSON/Plist, favicon loading, localStorage persistence

Phase 4 — Deployment
Vercel setup, custom domain (optional), GitHub Actions integration

Bonus

The environment/profile feature (see #15) can be built in from the start — localStorage makes per-environment persistence straightforward.

Alternatives Considered

• GitHub Pages: requires manual GitHub Actions configuration for React builds, no PR previews
• Netlify: viable alternative, but Vercel has better React/Vite defaults and is the de-facto standard for React deployments

Additional Context

• No backend needed — the tool is purely client-side logic
• The clean MVVM architecture of the existing Swift code maps well to React
• The only non-trivial port is Plist (Apple XML format) — the plist npm package handles this

Priority

Medium - Would improve workflow