feat(ui): persist JobLossGraph settings per job + fix chart height on control toggle

[MarcBate]

Summary

• Persist settings per job — display toggles (Smoothed, Raw, Log Y, Clip outliers), smoothing %, plot stride, per-series enabled state, and x-axis zoom range are saved to localStorage keyed by job ID (loss-graph:<id>). Settings are restored automatically when navigating back to a job's loss graph.
• Fix chart height jumping on Display button clicks — the post-creation setSize() call is now deferred to requestAnimationFrame so the browser completes layout before the legend height is measured, matching the behaviour of the existing ResizeObserver path.
• Restore zoom after chart recreation — when a display option is toggled (causing uPlot to recreate), any saved zoom range is re-applied after the new chart is sized. Reset zoom clears the saved range.

Test plan

• Open a job's loss graph, toggle Smoothed / Raw / Log Y, adjust Smoothing and Plot stride — verify chart height stays stable and controls don't cause it to resize.
• Set a custom zoom range by drag-selecting on the chart. Navigate away and back — verify the zoom is restored.
• Click Reset zoom — verify the full range is shown and the zoom is not re-applied on next visit.
• Verify settings persist across page refresh (F5) for the same job, and that two different jobs maintain independent settings.
• Verify series enabled/disabled state per job is restored correctly.

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