Add more viewer features

[dementive]

Summary

• Add configurable stock rendering with fixed dimensions, allowances, wall/floor stock, offsets, camera framing, and semantic wireframe edges. Allows viewer consumers to pass in custom stock geometry if they need to.
• Add direction-based face highlights, selection-driven X-ray focus, hover cards, and improved picking behavior.
• Add a section-plane gizmo with bidirectional dragging, physical cut measurement, and direction-coloured handles with theme overrides.
• Add the bundled banana-for-scale model and a shared controlled viewer toolbar component with reusable styling.
• Update the React viewer example and browser coverage for the new controls and interactions.
• Add different viewer control settings based on the user's preferred CAD program.

Public package release

• Changesets are included for @toolpath/viewer.
• No breaking changes.