Fix pre-existing Playwright E2E test failures to enable full suite in CI

[brianlan]

Background

PR #297 added a Playwright E2E CI job scoped to tests/graph-sandbox-security.spec.ts only, because the remaining E2E specs have pre-existing failures that would make the CI job red.

Current State

When running the full npm run test:ui suite in CI (with proper MongoDB + S3 infrastructure):

• 40 tests pass
• 7 tests fail (all pre-existing, unrelated to PR Add Playwright E2E tests to CI pipeline #297)

Failing Tests

Spec	Failed Tests	Error
practice.spec.ts	1	toHaveURL assertion failed
theme.spec.ts	6	strict mode violation: getByRole(\'button\', { name: \'Problems\' }) resolved to 2 elements (app shell + tags page + active practice page themes)

Local Reproduction

1. Start infrastructure: docker compose up -d mongodb rustfs and docker compose --profile bootstrap run --rm rustfs-bootstrap
2. Run full suite: cd frontend && npm run test:ui

Goal

Fix these 7 pre-existing test failures so the CI job in .github/workflows/pr-checks.yml can be expanded from:

to:

Acceptance Criteria

• All Playwright E2E tests pass locally with npm run test:ui
• The CI job runs the full suite without failures
• PR Add Playwright E2E tests to CI pipeline #297 is updated (or a follow-up PR created) to remove the -- tests/graph-sandbox-security.spec.ts scoping

Related

• Blocks: expanding the Playwright CI job to the full E2E suite
• Related to: Add Playwright E2E tests to CI pipeline #296 (Add Playwright E2E tests to CI pipeline)

[brianlan]

I’m starting work on this issue now. Plan: reproduce the full Playwright failures, fix only the pre-existing test/app issues needed for the full suite to pass, then expand the CI Playwright job back to the full suite and open a focused PR.