[Eng] Experiment: Add guided walkthrough to the pipeline editor

Placeholder development issue for #334657 (closed) based on design #334659 (closed)

Experiment

Experiment Summary

Design

• Control:
• Variant:

Rollout strategy

Inclusions and exclusions

Tracking Details

Actions we want to track:

Implementation checklist

• Update Suggest Pipeline banner CTA to redirect users to Pipeline Editor instead of Single File Editor (!73514 (merged))
• Update pipeline editor sidebar default expanded state to false (!73050 (merged))
• Show a popover guiding the user to commit. Clicking on the CTA button in the popover should auto-scroll to the commit form at the bottom of the screen (!73050 (merged))
• Implement tracking (!74063 (merged))