Add payment collection or deposit flow during document acceptance

[jusso-dev]

Context

ScopeStack can create Xero invoices, but the client portal does not yet support payment collection during acceptance. PandaDoc-style tools often combine proposal acceptance with deposit/payment collection.

Goal

Allow clients to pay a deposit or invoice as part of the document acceptance workflow.

Scope

• Configure payment requirement per document:
  • No payment.
  • Deposit amount or percentage.
  • Full amount.
  • External invoice payment link.
• Show payment step in client portal before or after acceptance depending on configuration.
• Integrate with a payment provider or start with Xero invoice payment links if available.
• Record payment status on the document.
• Include payment status in audit/completion evidence.

UX Notes

• The client-facing flow should be explicit: review, accept/sign, pay if required.
• Sender should see payment status on document detail.
• Avoid blocking acceptance accidentally when payment provider is unavailable unless the document requires payment.

Data/Architecture Notes

Potential fields:

• Document.paymentRequired
• Document.paymentMode none/deposit/full/invoice_link
• Document.depositAmount or depositPercent
• Document.paymentStatus
• Document.paymentProvider
• Document.paymentReference

Potential integrations:

• Stripe Checkout for direct payment.
• Xero online invoice URL if available from invoice creation.

Acceptance Criteria

• Sender can configure payment requirement for a document.
• Client portal displays required payment step.
• Payment completion updates document payment status.
• Audit logs record payment initiation/completion/failure.
• Completion certificate/evidence includes payment status.
• Xero invoice workflow remains compatible.

Dependencies

• Quote builder improves final payable totals.
• Completion certificate should include payment evidence.

Priority

P2. Strong commercial feature, best after core signing and document control are stable.