Add invoice payment celebration sharing

[Kingsman-99]

Label: complexity: high
Points: 200

Description

After fully funding an invoice, there is no way to celebrate or share the achievement. This issue adds a "Share Achievement" flow that appears when a payment completes an invoice, generating a shareable image card with the invoice ID, total amount, and a "Fully Funded!" badge for social media.

Technical Context

Involves invoice/[id]/page.tsx and a new src/components/AchievementCard.tsx. Detect when invoice.status transitions to Released after a payment. Render achievement card as a styled div and use html2canvas to export as PNG. Share via Web Share API or download. Add html2canvas to package.json.

Acceptance Criteria

• Achievement card appears when invoice transitions to Released
• Card shows invoice ID, total amount, and "Fully Funded!" badge
• "Share" button uses Web Share API on mobile
• "Download" button saves card as PNG via html2canvas
• html2canvas added to package.json
• Mobile responsive — works on 375px screens
• No TypeScript errors

[Bruno755]

@Bruno755 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

i would like to apply to this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Bruno755 to this issue.

[drips-wave]

Congratulations, @Bruno755! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @Bruno755: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

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[drips-wave]

This issue has been completed by @Bruno755 as part of the Stellar Wave Program's 5th Wave 🥳

😎 @Bruno755: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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