Implement subscription payment method management with multiple tokens

[Smartdevs17]

Description

Users need to manage multiple payment methods across different tokens and chains. Build a payment method management system with priority ordering.

Acceptance Criteria

• Multi-payment-method storage per user
• Payment method priority (primary, backup, fallback)
• Token type support (XLM, USDC, ETH, native token)
• Payment method validation and verification
• Automatic fallback on primary payment failure
• Payment method expiry tracking and notification

Technical Scope

• src/services/walletService.ts
• src/store/walletStore.ts
• contracts/subscription/src/lib.rs
• Edge: token balance insufficient at charge time, gas price spikes, token contract upgrade

[Junman140]

@Junman140 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I would want to work on this project because ive being contributing to pi network and stellar for 6 years now and i use mainly typescript, rust and javascript

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Junman140 to this issue.

[drips-wave]

Congratulations, @Junman140! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @Junman140: 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

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