Add plain text clipboard transfers and refine input feedback

tests/e2e/nearby.mjs

@@ -117,8 +117,8 @@ try {
     };
   });
   await sender.locator('.peer-card').first().click();
-  await sender.getByRole('button', { name: '대신 링크 붙여넣기', exact: true }).click();
-  await sender.getByLabel('보낼 URL').fill('https://example.com/nearby');
+
+  await sender.locator('.current-url, .current-text').fill('https://example.com/nearby');
   await sender.getByRole('button', { name: '전송하기', exact: true }).click();
   const opened = receiver.waitForEvent('popup');
   void opened.catch(() => {});