Move pipelines page to GraphQL - Part 2

What does this MR do and why?

Part one - !206072 (merged) ✅

Part two - YOU ARE HERE 😄

Goal: Move Build > Pipelines to use GraphQL as the SSOT for data. In part two we add support for the pipeline mini graph and actions.

References

Screenshots or screen recordings

How to set up and validate locally

1. First visit Build > Pipelines and ensure existing feature works as expected.
2. Next enable Feature.enable(:pipelines_page_graphql) feature flag
3. Visit Build > Pipelines again
4. Ensure the Stages and Actions columns work for the table in this MR. The Actions column is not functional yet just displaying. Will fix in later MRs.
5. It's okay that the rest is missing and broken, we are iterating here

MR acceptance checklist

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Related to #223264