fix(checkout): stop expiry timer after settlement

[Alike001]

Summary

• replace the expiry countdown with a Paid badge after paid or overpaid settlement
• disable the wallet payment action once payment has already been received
• preserve active and expired countdown behavior before settlement
• add component and integration regression coverage for polled and refreshed paid states

Verification

• formatting passed
• lint passed
• type-check passed
• focused component/integration suite: 12 passed
• secret scan passed
• production build passed
• Playwright captured the current production page as before-fix evidence; post-deployment rendered verification will use the same checkout

Closes #41

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Project	Deployment	Actions	Updated (UTC)
zecceipt	Ready	Preview	Aug 30, 2026 5:25pm