feat: add server settings for default board, default color scheme and default locale (#1373)

* feat: add server settings for default board, default color scheme and default locale

* chore: address pull request feedback

* test: adjust unit tests to match requirements

* fix: deepsource issue

* chore: add deepsource as dependency to translation library

* refactor: restructure language-combobox, adjust default locale for next-intl

* chore: change cookie keys prefix from homarr- to homarr.

apps/nextjs/src/theme/color-scheme.ts

@@ -0,0 +1,18 @@
+import { cache } from "react";
+import { cookies } from "next/headers";
+
+import { db } from "@homarr/db";
+import { getServerSettingByKeyAsync } from "@homarr/db/queries";
+import type { ColorScheme } from "@homarr/definitions";
+import { colorSchemeCookieKey } from "@homarr/definitions";
+
+export const getCurrentColorSchemeAsync = cache(async () => {
+  const cookieValue = cookies().get(colorSchemeCookieKey)?.value;
+
+  if (cookieValue) {
+    return cookieValue as ColorScheme;
+  }
+
+  const appearanceSettings = await getServerSettingByKeyAsync(db, "appearance");
+  return appearanceSettings.defaultColorScheme;
+});