Improve Playwright test patterns in XComsPage.ts to align with best practices.

• Replace page.locator('[data-testid="..."]') with page.getByTestId()
• Replace locator('[role="..."]') with getByRole()
• Replace CSS filter({ hasText }) on th with getByRole("columnheader", { name })
• Replace locator("input") with getByRole("textbox")
• Replace manual assertions (expect(count).toBeGreaterThan(0)) with web-first assertions (await expect(rows).not.toHaveCount(0))
• Replace textContent() manual checks with not.toHaveText("")
• Replace page.evaluate()-style DOM queries with locator-based .or() chains
• Extract reusable tableRows locator to reduce repetition

closes: #63966