feat(library): add the merge duplicate dialog

src/pages/GameDetail.test.jsx

@@ -257,6 +257,15 @@ describe('GameDetail of a game added by hand', () => {
             expect(await screen.findByText('CORRECTION.TITLE')).toBeTruthy();
         });
 
+        it('offers "merge duplicate" to an active auditor', async () => {
+            loggedInAs({role: 'AUDITOR', activeRole: 'AUDITOR'});
+            renderDetail();
+
+            fireEvent.click(await screen.findByRole('button', {name: 'MERGE.OPEN'}));
+
+            expect(await screen.findByText('MERGE.TITLE')).toBeTruthy();
+        });
+
         it('offers nothing to a user or to an admin viewing as user', async () => {
             for (const me of [{role: 'USER', activeRole: 'USER'}, {role: 'PLATFORM_ADMIN', activeRole: 'USER'}]) {
                 loggedInAs(me);
@@ -267,6 +276,7 @@ describe('GameDetail of a game added by hand', () => {
                 // Let the answer of /me reach the page before looking for the button.
                 await act(async () => {});
                 expect(screen.queryByRole('button', {name: 'CORRECTION.OPEN'})).toBeNull();
+                expect(screen.queryByRole('button', {name: 'MERGE.OPEN'})).toBeNull();
                 cleanup();
             }
         });