Add reduced-motion variant for confetti success animations

[greatest0fallt1me]

Description

This is a UI/UX issue for the GrantFox campaign. This is a UI/UX issue for the GrantFox campaign. Static success state under prefers-reduced-motion.

Requirements and Context

• Implement per the description
• Add focused tests for the change
• Document any API/visible changes
• Adhere to repo's lint and code style
• 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 task/confetti-reduced

2. Implement changes
   • app/components/SuccessConfetti.tsx
   • app/styles/motion.css
3. Test and commit
   • Run the repo's standard test suite and lint
   • Cover edge cases; include output in the PR

Example commit message

fix: reduced-motion confetti

Acceptance Criteria

• Implementation matches the description
• Tests added and passing
• Code review approved
• Docs updated

Guidelines

• Responsive across all breakpoints
• WCAG 2.1 AA accessibility
• Design-token + dark-mode consistency
• Clear documentation and inline comments
• Timeframe: 96 hours

[MaimunaY]

@MaimunaY has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi Maintainer, I am a SWE, and I'd like to fix and deliver issue #333. I have a clean, efficient fix ready to go. With your permission I'd be glad to resolve this issue. Thank you.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @MaimunaY to this issue.