feat(module): support i18n in components (#2553)

Co-authored-by: Benjamin Canac <canacb1@gmail.com>

src/runtime/composables/defineLocale.ts

@@ -0,0 +1,8 @@
+import type { Locale, LocalePair } from '../types/locale'
+
+export function defineLocale(name: string, pair: LocalePair): Locale {
+  return {
+    name,
+    ui: pair
+  }
+}

src/runtime/composables/useLocale.ts

@@ -0,0 +1,13 @@
+import { computed, inject, ref } from 'vue'
+import type { InjectionKey, Ref } from 'vue'
+import type { Locale } from '../types/locale'
+import { buildLocaleContext } from '../utils/locale'
+import { en } from '../locale'
+
+export const localeContextInjectionKey: InjectionKey<Ref<Locale | undefined>> = Symbol('nuxt-ui.locale-context')
+
+export const useLocale = (localeOverrides?: Ref<Locale | undefined>) => {
+  const locale = localeOverrides || inject(localeContextInjectionKey, ref())!
+
+  return buildLocaleContext(computed(() => locale.value || en))
+}