FE-1548: Rework the optimization and sweep drawer views

[kube]

Important

Experimental
Behind the Parameter sweeps and Optimization surface feature flags.
Section order and scrolling list ship for every experiment and study.

Summary

Before this PR, in the experiment and optimization result drawers the surface sat below the event list. Experiment drawer put it under the metric charts, optimization drawer under the steps. Whole drawer body scrolled, graphs included.

This PR reorders both drawers so the graphs come before the event lists. Summary, navigator and surface stay fixed above the list. Only the step or metric list scrolls, in its own container.

Links

• Ticket FE-1548
• Docs Experiments
• Docs Optimization

Changes

Drawer layout

• Optimization drawer orders Summary → Best parameters → Surface → Steps

  Surface previously sat below the steps.

• Experiment drawer orders Summary → Parameters → Surface → Metrics

  Surface previously sat below the metric charts.

• Drawer bodies no longer scroll as a whole

  Both are flex columns.
  Sections above the list are fixed.
  Steps table or metric grid scrolls in its own container and fills the remaining height.

• Steps table header stays pinned while the list scrolls

  Sticky element is the header's rowgroup. A sticky row can only move within its own rowgroup, which is exactly as tall as the row.

• Fixes clipped labels in the surface control row

  ds Select root's min-width: min-content overflowed its 170px box over the neighbouring "Y" and "Metric" labels.

Test coverage

• Existing @hashintel/petrinaut unit suite
• Storybook DOM probes and screenshots:

  List scrolls alone, drawer body holds still, table header stays pinned.

How to test

• Open Petrinaut preview on Vercel
• Viewport controls > Settings > Simulation > Parameter sweeps and Optimization surface
• Simulate > Experiments > Create
• Pick scenario, flip Sweep on two numeric parameters, Run
• Open experiment row
• Expect summary, sliders and surface hold still while only metric charts scroll
• Expect "Y" and "Metric" labels beside surface selects unclipped
• Studies need optimizer service, locally turbo run dev --filter @apps/petrinaut-website -- --with-optimizer-service
• Create study over two parameters, open its row
• Expect surface above steps, steps list scrolls in place, header row stays pinned

Demo

Screenshots pending, files handed over alongside this PR.

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[TimDiekmann]

re-approval of pre-rebase