feat(i18n): add Lingui runtime and development tooling

- add SSR-safe I18nProvider, Translate, locale hooks, catalog activation, and typed runtime APIs

- add consumer-owned Lingui configuration helpers and a CLI for locale creation, extraction, compilation, and project discovery

- add catalog read/write services plus a Vite development API plugin scoped to each consuming application

- add the portal-based I18nDevtool, message editor, dark-theme tracking, and standalone Message Studio

- document the consumer workflow and cover runtime, configuration, catalog, CLI, and Devtool behavior with tests

packages/i18n/src/runtime/hooks.ts

@@ -0,0 +1,54 @@
+import * as React from "react"
+import type { MessageDescriptor, MessageId, MessageOptions } from "@lingui/core"
+import { useLingui } from "@lingui/react"
+
+import { I18nRuntimeContext } from "./context"
+import type { LocaleDefinition, TranslateFunction } from "./types"
+
+export function useTranslate(): TranslateFunction {
+  return useLingui()._
+}
+
+export function useMessage(descriptor: MessageDescriptor): string
+export function useMessage(
+  id: MessageId,
+  values?: Record<string, unknown>,
+  options?: MessageOptions
+): string
+export function useMessage(
+  descriptorOrId: MessageDescriptor | MessageId,
+  values?: Record<string, unknown>,
+  options?: MessageOptions
+) {
+  const translate = useTranslate()
+
+  return React.useMemo(
+    () =>
+      typeof descriptorOrId === "string"
+        ? translate(descriptorOrId, values, options)
+        : translate(descriptorOrId),
+    [descriptorOrId, options, translate, values]
+  )
+}
+
+export function useLocale(): string {
+  const runtime = React.useContext(I18nRuntimeContext)
+  const { i18n } = useLingui()
+
+  return runtime?.locale ?? i18n.locale
+}
+
+export function useLocales(): readonly LocaleDefinition[] {
+  const runtime = React.useContext(I18nRuntimeContext)
+  const { i18n } = useLingui()
+
+  return (
+    runtime?.locales ?? [
+      {
+        direction: "ltr",
+        label: i18n.locale,
+        locale: i18n.locale,
+      },
+    ]
+  )
+}