Replace Cypress with Playwright

The single Cypress spec is slow and flaky by design: hardcoded cy.wait() calls throughout and it depends on live Spotify search results for its test data. Playwright's auto-waiting removes the sleeps, and seeded fixtures remove the network dependency.

• Port the create-review flow to Playwright: login, search, fill the form, submit, verify the album and artist pages
• Test data comes from the seeder, not live Spotify (mock the Spotify endpoints or seed an unreviewed album)
• No fixed waits anywhere, rely on auto-waiting and web-first assertions
• Remove cypress and its config