Experiment viewer interface update

[Dagonite]

Closes #552, closes #672, closes #684.

Description

• Updates experiment viewer UI to be more legible, particularly in dark mode.
• Expands the 1D graph toolbar with Y-range controls, X/Y scale selectors, grid and error bar toggles, and curve/interpolation options.
• Improves graph rendering robustness by handling mixed-length series more safely.
• Updates Cypress config.
• Migrates test runner from Jest to Vitest.
• Adds Vitest coverage for the graph toolbar and verifies domain, scale, and style control behaviour.

[Pasarus]

Just a couple initial questions