fix: improve accessibility in DailyNoteWidget (#2560)

[aaniya22]

Summary

Replaced a clickable <p> tag with a proper <button> for the yesterday-note toggle in DailyNoteWidget, and added an aria-label to the note textarea for screen reader users.

Closes #2560

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Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)

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What Changed

• Changed the "Yesterday you planned to:" toggle from a <p onClick> to a semantic <button type="button"> in src/components/DailyNoteWidget.tsx
• Added aria-label="Today's coding plan" to the auto-save textarea
• Reviewed the auto-save hook's dependency array — debounceFunction is already correctly memoized with useCallback([note]) and included in the effect's deps; no change needed there

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How to Test

1. Open the Daily Note widget on the dashboard
2. Tab through the widget using only the keyboard
3. Confirm the "Yesterday you planned to:" toggle can be focused and activated with Enter/Space, and that a screen reader announces the textarea's purpose

Expected result: Toggle is keyboard-focusable and operable as a button (not just clickable), and the textarea has an accessible name.

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Screenshots / Recordings

N/A — visual appearance unchanged, only semantics/accessibility improved.

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Checklist

• Linked the related issue above
• Self-reviewed my own diff
• No unnecessary console.log, debug code, or commented-out blocks
• npm run lint passes locally
• No TypeScript errors (npm run type-check)
• Added or updated tests where applicable
• Updated documentation / comments if behavior changed

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Accessibility (UI changes only)

• Keyboard navigation works correctly
• Color contrast meets WCAG AA standard
• ARIA labels / roles added where needed
• Tested on mobile / responsive layout

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Additional Context

None.

[github-actions]

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