feat(models): add axis scaling and chart stretch controls to model comparison

[atomantic]

Summary

On the Model Comparison page, models can easily cluster together and overlap, making data points and labels difficult to read. This adds:

• Horizontal Chart Stretch Controls: Ability to stretch the chart width (1×, 1.5×, 2×, 3×) with smooth horizontal scrolling and click-and-drag panning, allowing dense data clusters to spread out physically across the canvas.
• Chart Height Controls: Preset height adjustments (480px, 600px, 720px) to provide more vertical space between models.
• Axis Scaling & Zooming:
  • Quick Zoom In (+) and Zoom Out (-) buttons that zoom centered on the data.
  • 'Fit visible' button that tightly bounds the active models.
  • 'Reset zoom' button restoring automatic extents.
  • Expandable 'Scale axes' form with explicit numeric inputs for Cost (Min $, Max $) and Quality Score (Min, Max) with 'Apply range' and 'Clear range'.
  • Support for clipping points and suppressing labels outside the zoomed viewport (allowDataOverflow).
• URL Parameter Sync: Persists stretch, height, xMin, xMax, yMin, yMax in query params so views can be shared and bookmarked.

Test plan

• Run unit tests: npm test src/components/models/ModelComparison.test.jsx (10 passing tests verifying stretching, height, zoom in/out/reset, fit visible, manual range inputs, and URL params).
• Run client test suite: npm test in client (866 test files passed, 10,555 tests passed).
• Run linter: npm run lint in client (no issues found).
• Run build: npm run build in client (build passes cleanly).