Unify dynamic locale routing

tests/locale.test.ts

@@ -0,0 +1,22 @@
+import { describe, expect, it } from "vitest";
+
+import { getLocalizedPathWithDefault } from "../lib/locale";
+
+describe("locale path helpers", () => {
+  it("keeps the configured default locale on the bare domain", () => {
+    expect(getLocalizedPathWithDefault("ar", "/", "ar")).toBe("/");
+    expect(getLocalizedPathWithDefault("de", "/", "ar")).toBe("/de");
+    expect(getLocalizedPathWithDefault("en", "/", "ar")).toBe("/en");
+  });
+
+  it("builds nested paths against the configured default locale", () => {
+    expect(getLocalizedPathWithDefault("ar", "/coming-soon", "ar")).toBe("/coming-soon");
+    expect(getLocalizedPathWithDefault("de", "/coming-soon", "ar")).toBe("/de/coming-soon");
+    expect(getLocalizedPathWithDefault("en", "/portfolio", "de")).toBe("/en/portfolio");
+  });
+
+  it("strips old locale prefixes before rebuilding the target path", () => {
+    expect(getLocalizedPathWithDefault("en", "/ar/contact", "de")).toBe("/en/contact");
+    expect(getLocalizedPathWithDefault("ar", "/de/about", "ar")).toBe("/about");
+  });
+});