docs: ship in-house RN checkout, scope 5 follow-up tasks (#7-11)

In-house Request Network checkout went fully end-to-end on dev today.
A real 0.01 USDC payment flowed through wallet connect -> approve ->
ERC20FeeProxy.transferFromWithReferenceAndFee -> RN webhook ->
TransactionSafetyProvider -> Payment.status=completed -> page success
state. Tx 0x494c77a29161b5100d8e0b1ac675f1822955d0bb3633ecdbfafb886f84f2f320.

Docs:
- New PRD: Wallet, Multichain, Confirmations, AML, Trezor
  (5 follow-ups, each sized for an independent contributor)
- Updated PRD: Request Network In-House Checkout (phases 0..3 done,
  phase 4 partial, phases 5-6 not started)
- Updated handoff: deployed versions, what is working end-to-end,
  follow-up tasks index

Taskmaster: 5 new top-level tasks (#7..#11) covering ephemeral
destination wallets, multichain proxy registry + USDC/USDT, runtime
confirmation thresholds, optional seller-paid AML screening, and
Trezor signing for admin actions. Tasks are scoped fine-grained so
each is independent enough for kimi to pick up.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Taskmaster/Tasks/task-6-1.md

@@ -0,0 +1,35 @@
+---
+taskmaster_id: "6.1"
+status: "done"
+priority: "high"
+depends_on: []
+parent_id: "6"
+source: "taskmaster"
+generated_at: "2026-05-28T11:49:27.076Z"
+---
+
+# 6.1 - Deploy confirmation repair before next paid probe
+
+- [x] 6.1 - Deploy confirmation repair before next paid probe #taskmaster #priority/high #status/done ⏫ 🆔 tm-6-1
+
+## Metadata
+
+| Field | Value |
+| --- | --- |
+| Taskmaster ID | 6.1 |
+| Status | done |
+| Priority | high |
+| Dependencies | None |
+| Parent | 6 - Request Network in-house checkout (Rabby-supporting) |
+
+## Description
+
+2026-05-28 dev BSC transaction succeeded and RN delivered four webhooks, but Amanat returned 404 due Request Network reference-correlation mismatch. Before another paid payment test, deploy the backend correlation fix, callback polling fix, signed-webhook smoke test, and Transaction Safety Provider gate; then repeat the probe and inspect safety decision state.
+
+## Details
+
+_No details._
+
+## Verification
+
+_No verification strategy._