Design a "Quiet hours" preference that suppresses non-critical toasts and animations

[greatest0fallt1me]

Description

This is a UI/UX issue introducing a Quiet hours preference under Settings → Notifications that suppresses non-critical toasts and freezes ambient animations within a user-defined window. Critical alerts (wallet errors, claim failures) still surface.

Requirements and Context

• Stored as { start: "22:00", end: "08:00", tz: "auto" }
• Hook in components/ui/toast.tsx and sonner.tsx to filter by severity
• Visual indicator in the navbar moon icon
• Must be secure, tested, and documented
• Should be efficient and easy to review

Suggested Execution

1. Fork the repo and create a branch

   git checkout -b feature/quiet-hours

2. Implement changes
   • Edit app/(dashboard)/settings/page.tsx
   • Add lib/quiet-hours.ts and integrate with toast surfaces
3. Test and commit
   • Time-fake tests around boundary
   • Cover edge cases (timezone changes, DST)
   • Include test output and notes in the PR

Example commit message

feat: quiet hours preference for toasts and motion

Acceptance Criteria

• Critical toasts bypass quiet hours
• Boundary handling (across midnight) verified
• Indicator visible when active

Guidelines

• WCAG 2.1 AA, never block actionable warnings
• Clear documentation and inline comments
• Timeframe: 96 hours