Add UI E2E testing framework with Playwright and Breeze integration

[vatsrahul1001]

Adds UI end-to-end testing framework using Playwright, integrated with Breeze.

• New breeze testing ui-e2e-tests command for UI automation tests
• Page Object Model structure for maintainable tests
• Initial test: DAG trigger workflow with verification

breeze testing ui-e2e-tests --test-pattern "dag-trigger.spec.ts" --headed

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[pierrejeambrun]

Amazing! 🎉

Just a few suggestion / improvement but I think this is a solid base!

[pierrejeambrun]

We probably also should git ignore reports and test results

[pierrejeambrun]

I'm having trouble running all 3 on my end.

It's a bit flaky. Basically commands without the --project options are broken.

All green

Some errors (but I can't reproduce consistently)

When I run them separately with:

breeze testing ui-e2e-tests --browser firefox --headed

All 3 are working.

Just a few adjustments and we can merge. We will see the flakiness when we integrate this to the CI.

[jscheffl]

Cool!

#protm

[potiuk]

This is cool.

But there are two follow up questions:

• Currently breeze testing ui-e2e-tests fails when there is no pnpm installed locally:

  File "/Users/jarekpotiuk/.local/share/uv/python/cpython-3.13.7-macos-aarch64-none/lib/python3.13/subprocess.py", line 1972, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'pnpm'

I think it should at least be explained as a prerequisite or installed automatically. Generally breeze testing is a command that does everything - lile building images when needed etc. Might be a good idea to improve that part

• the tests are not run in CI (I guess?) - this means that they are prone to be broken any time. Any plans to run them on CI ?

[vatsrahul1001]

Thanks for raising this @potiuk I will raise PR to handle this today.

• Currently breeze testing ui-e2e-tests fails when there is no pnpm installed locally:

Yes, the plan is to create a CI workflow that will deploy an Airflow instance and run these tests. I will create a follow-up PR for this soon.
the tests are not run in CI (I guess?) - this means that they are prone to be broken any time. Any plans to run them on CI ?

[vatsrahul1001]

PR to install pnpm if not already installed.