fix: restore Pattern.prototype.base_url via afterEach in navigation tests

Agent-Logs-Url: https://github.com/Patternslib/Patterns/sessions/49709a1a-a4ed-4d5c-aac9-6c685d170fd5

Co-authored-by: thet <170891+thet@users.noreply.github.com>

Author: Copilot

src/pat/navigation/navigation.test.js

@@ -227,15 +227,21 @@ describe("2 - Navigation pattern tests - mark after navigation injection", funct
 
 describe("3 - Navigation pattern tests - Mark items based on URL", () => {
     let _window_location;
+    let _originalBaseUrl;
 
     beforeEach(() => {
         _window_location = global.window.location;
         delete global.window.location;
         document.body.innerHTML = "";
+        _originalBaseUrl = Pattern.prototype.base_url;
+        Pattern.prototype.base_url = function () {
+            return "https://patternslib.com/";
+        };
     });
 
     afterEach(() => {
         global.window.location = _window_location;
+        Pattern.prototype.base_url = _originalBaseUrl;
     });
 
     it("navigation roundtrip", async () => {
@@ -281,12 +287,6 @@ describe("3 - Navigation pattern tests - Mark items based on URL", () => {
           </nav>
         `;
 
-        // Mock the base_url method at the prototype level to avoid JSDOM navigation issues
-        const originalBaseUrl = Pattern.prototype.base_url;
-        Pattern.prototype.base_url = function () {
-            return "https://patternslib.com/";
-        };
-
         // Set portal URL directly on document body
         document.body.dataset.portalUrl = "https://patternslib.com";
 
@@ -372,9 +372,6 @@ describe("3 - Navigation pattern tests - Mark items based on URL", () => {
         expect(document.querySelectorAll(".current").length).toBe(2);
         expect(document.querySelectorAll(".inPath").length).toBe(0);
         expect(document.querySelector(".current a")).toBe(it4);
-
-        // Restore the original method
-        Pattern.prototype.base_url = originalBaseUrl;
     });
 });