phsl / new-api

* Introduced a currency switch to toggle prices between USD and CNY.
  * CNY prices are calculated by multiplying USD prices with the site-wide `price` rate from `/api/status`.
* Added a second switch to display prices per 1 M tokens or per 1 K tokens.
  * When “K” is selected, prices are divided by 1 000 and labels are updated accordingly.
* Extended component state with `currency` and `tokenUnit` variables.
* Integrated `StatusContext` to retrieve and memoize the current exchange rate.
* Updated price rendering logic and labels to reflect selected currency and token unit.
* Minor UI tweaks: kept Switch components compact and aligned with the table header.

No breaking changes.