feat(web): scaffold client-side rendered SPA foundation

- feat: initialize Vite project with React 19, React Router 8, TanStack
  Query, Ant Design 6, and Tailwind CSS 4
- feat: add Oxlint with React/TypeScript rules, strict TypeScript
  config, and layered CSS import order
- docs: add decision record for client-rendered Web foundation with
  React, Ant Design, and Tailwind CSS
- docs: create web roadmap defining architecture boundaries and deferred
  dependencies
- build: pin Node.js 24 in mise.toml

web/vite.config.ts

@@ -0,0 +1,7 @@
+import { defineConfig } from 'vite'
+import react from '@vitejs/plugin-react'
+import tailwindcss from '@tailwindcss/vite'
+
+export default defineConfig({
+  plugins: [react(), tailwindcss()],
+})