🎨 Palette: Improve accessible input labels for Screen Readers

[dieterolson]

💡 What: Added dynamic IDs linking labels to inputs and context-aware ARIA labels to mathematical matrix grids across the Rotation Converter.
🎯 Why: Previously, inputs lacked linked labels or individual descriptors in grid mappings, causing severe accessibility barriers for screen reader users trying to navigate mathematical operations.
📸 Before/After: N/A - pure screen reader structural enhancement without visual UI changes.
♿ Accessibility: Ensures full keyboard and screen reader accessibility by properly announcing input contexts and dynamically linking grouped form field controls.

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PR created automatically by Jules for task 4660551570368348091 started by @dieterolson

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