nextjs-locale-standalonelisted

# Next.js locale routing — standalone site Locale-prefixed routing for one Next.js App Router app, no shared package. Every page lives under `/<locale>/…`; a proxy (middleware) sends unprefixed requests to the right locale. Drop-in copy-paste files are in [`templates/`](./templates). > Sibling skill: **nextjs-locale-monorepo** — the same behaviour factored into a > shared workspace package for multi-app repos. Keep the two in sync. ## The behaviour (the spec both skills implement) - **URLs are locale-namespaced:** `/en-hk/about`, `/zh-hk/about`. One locale is the default. - **The proxy redirects unprefixed paths.** A request to `/about` (or `/`) with no known locale prefix is 307-redirected to `/<locale>/about`, preserving the query string. (URL hashes are client-side only — they never reach the server, so the proxy can't and needn't carry them; the LocaleToggle, running in the browser, does preserve the hash.) The locale is resolved by this **priority**: 1. **`NEXT_LOCALE` cookie** — the toggle's last choice (if the visitor has ever switched). 2. **`Accept-Language`** — the browser's preferred language (exact match, then language-only, e.g. `zh` → `zh-hk`). 3. **Default locale.** - **Already-prefixed paths pass through** (`NextResponse.next()`), and the proxy stamps the response: `x-locale` header and a (re)write of `NEXT_LOCALE` when it differs. It does **not** add `Vary: Accept-Language, Cookie` here — on a prefixed path the locale is fixed by the