🎨 Palette: Add aria-label to icon-only buttons in Dashboard

[julwrites]

Added aria-label attributes to the icon-only buttons in web/src/pages/Dashboard.tsx to improve accessibility for screen readers.

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PR created automatically by Jules for task 9116164657490866150 started by @julwrites

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[github-actions]

Code Coverage Report

Component	Metric	Percentage
Backend	Total	84.0%
Frontend	Statements	72.84%
Frontend	Branches	58.91%
Frontend	Functions	69.6%
Frontend	Lines	75.4%