Add coverage prettification and sorting functionality

- Introduced `prettify.css` for syntax highlighting in coverage reports.
- Added `prettify.js` to handle code formatting and highlighting.
- Included `sort-arrow-sprite.png` for sort indicators in the coverage table.
- Implemented `sorter.js` to enable sorting and filtering of coverage summary tables.
- Added a search box for filtering table rows based on user input.

ccw/frontend/src/pages/EndpointsPage.test.tsx

@@ -71,8 +71,7 @@ describe('EndpointsPage', () => {
   beforeEach(() => {
     vi.clearAllMocks();
     // confirm() used for delete
-    // @ts-expect-error - test override
-    global.confirm = vi.fn(() => true);
+    vi.stubGlobal('confirm', vi.fn(() => true));
   });
 
   it('should render page title', () => {
@@ -128,4 +127,3 @@ describe('EndpointsPage', () => {
     });
   });
 });
-