Internationalization + Finnish language (#181)

* I18n with next-intl

* package-lock

* Finnish translations

* Development fix

* Use locale for positioning currency symbol

* Translations: Expenses.ActiveUserModal

* Translations: group 404

* Better translation for ExpenseCard

* Apply translations in CategorySelect search

* Fix for Finnish translation

* Translations for ExpenseDocumentsInput

* Translations for CreateFromReceipt

* Fix for Finnish translation

* Translations for schema errors

* Fix for Finnish translation

* Fixes for Finnish translations

* Prettier

---------

Co-authored-by: Sebastien Castiel <sebastien@castiel.me>

src/i18n.ts

@@ -0,0 +1,16 @@
+import { getRequestConfig } from 'next-intl/server'
+import { getUserLocale } from './lib/locale'
+
+export const locales = ['en-US', 'fi'] as const
+export type Locale = (typeof locales)[number]
+export type Locales = ReadonlyArray<Locale>
+export const defaultLocale: Locale = 'en-US'
+
+export default getRequestConfig(async () => {
+  const locale = await getUserLocale()
+
+  return {
+    locale,
+    messages: (await import(`../messages/${locale}.json`)).default,
+  }
+})