🎨 Palette: Add ARIA labels to dynamic matrix grids

[dieterolson]

💡 What: Added dynamic aria-label attributes to the matrix and vector input fields in ReferenceFrameConverter.tsx and RotationConverter.tsx.
🎯 Why: Dynamic input grids are completely inaccessible to screen reader users without explicit labels for each cell. Because standard <label> elements are impractical for dense matrix layouts, aria-label provides the necessary context.
📸 Before/After: Inputs for matrices and vectors had no screen reader announcements. Now they clearly announce their mathematical component (e.g. "Transform matrix row 1, column 1", "Twist component ωx", or "Quaternion component W").
♿ Accessibility: Significantly improves screen reader navigation by explicitly associating matrix cells and vector elements with their contextual meaning.

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PR created automatically by Jules for task 3953280844180552522 started by @dieterolson

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