feat(ui): add framework-neutral localization support

- add a lightweight UI i18n provider with translation and locale contexts\n- localize accessibility labels across breadcrumb, carousel, dialog, pagination, sheet, sidebar, spinner, and toast components\n- integrate calendar locale data without coupling UI components to Lingui\n- publish tree-shakeable catalogs for eight common locales

packages/ui/src/i18n/catalogs.ts

@@ -0,0 +1,33 @@
+export const uiCatalogLocales = [
+  "de",
+  "en",
+  "es",
+  "fr",
+  "ja",
+  "ko",
+  "zh-Hans",
+  "zh-Hant",
+] as const
+
+export const uiMessageIds = [
+  "ui.breadcrumb.label",
+  "ui.carousel.nextSlide",
+  "ui.carousel.previousSlide",
+  "ui.common.close",
+  "ui.common.loading",
+  "ui.common.more",
+  "ui.pagination.label",
+  "ui.pagination.more",
+  "ui.pagination.next",
+  "ui.pagination.nextPage",
+  "ui.pagination.previous",
+  "ui.pagination.previousPage",
+  "ui.sidebar.description",
+  "ui.sidebar.title",
+  "ui.sidebar.toggle",
+  "ui.toast.close",
+] as const
+
+export type UiCatalogLocale = (typeof uiCatalogLocales)[number]
+export type UiMessageId = (typeof uiMessageIds)[number]
+export type UiMessageCatalog = Readonly<Record<UiMessageId, string>>