Implement data import from external subscription platforms

[Smartdevs17]

Description

Build an import system that allows merchants to migrate subscriptions from external platforms (Stripe, Chargebee, Recurly) via CSV/API import with validation.

Acceptance Criteria

• CSV import with column mapping wizard
• API-based import from Stripe and Chargebee
• Import validation with error reporting
• Duplicate detection and merge strategy
• Import progress tracking
• Rollback on import failure

Technical Scope

• src/screens/ImportScreen.tsx
• src/utils/importExport.ts
• backend/services/
• Edge: data format differences across platforms, ID collision, timezone handling

[Johnjnr1]

@Johnjnr1 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi, I'd like to work on this issue! because I am very conversant with solving problems like this!

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Johnjnr1 to this issue.

[drips-wave]

Congratulations, @Johnjnr1! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @Johnjnr1: 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.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊