feat(lang): add Finnish language support

- Add fi locale configuration to localeConfigurations in config.ts
- Add fi.json translation file (based on en.json, to be translated via Crowdin)
- Finnish uses dayjs/locale/fi and mantine-react-table MRT_Localization_FI

packages/translation/src/config.ts

@@ -140,6 +140,17 @@ export const localeConfigurations = {
       return import("dayjs/locale/et").then((module) => module.default);
     },
   },
+  fi: {
+    name: "Suomi",
+    translatedName: "Finnish",
+    icon: flagIcon("fi"),
+    importMrtLocalization() {
+      return import("mantine-react-table/locales/fi/index.esm.mjs").then((module) => module.MRT_Localization_FI);
+    },
+    importDayJsLocale() {
+      return import("dayjs/locale/fi").then((module) => module.default);
+    },
+  },
   fr: {
     name: "Français",
     translatedName: "French",