Add core-side synthetic destination for swap-to-address

[j0ntz]

CHANGELOG

Does this branch warrant an entry to the CHANGELOG?

• Yes
• No

Dependencies

none

Description

Asana task

Production implementation of swap-to-address (the core piece of Stealth Send / send-to-any-asset). EdgeSwapRequest accepts an optional toAddressInfo descriptor as an alternative to toWallet (exactly one of the two required); the core builds a synthetic, bridgified destination wallet from it, backed by the real currencyConfig, so swap plugins receive an EdgeCurrencyWallet unchanged. Nothing Houdini-specific lives in core: the same mechanism powers provider-agnostic send-to-any-asset (verified in-app with a ChangeNOW-routed cross-chain send).

Judgement calls, with alternates:

• Slim descriptor. EdgeSwapToAddressInfo carries only toPluginId, toAddress, and optional toMemos. toPluginId selects the currencyConfig (not derivable from the request); toAddress is the payload; the destination token comes from the request's own toTokenId. Alternate (descriptor carrying toTokenId) was rejected as a two-sources-of-truth hazard.
• Destination memos ride getMemos on the synthetic wallet. For memo-required payout chains (e.g. an XRP destination tag), the descriptor's toMemos is only the GUI-to-core transport; plugins never read the descriptor. The synthetic wallet exposes getMemos() (EdgeSyntheticDestinationWallet), so the plugin-facing mechanism stays wallet-shaped. Alternate (plugins reading a tag field off the request descriptor) was rejected to keep the plugin interface generic. A pure no-descriptor design is not physically possible: the value must cross the GUI-core bridge somewhere, and the descriptor is the plain-data channel that crosses yaob cleanly.
• EdgeTxActionSwap.payoutWalletId and EdgeTxSwap.payoutWalletId are both optional now. A swap-to-address destination has no payout wallet; payoutAddress carries the destination. Making only the action type optional (the prototype state) left a latent inconsistency in EdgeTxSwap. Alternate (keeping them required and writing the synthetic synthetic://<pluginId> id) was rejected: it embeds fake wallet ids in persistent tx metadata.
• Log privacy. Both swap-quote logging paths redact the pasted destination address AND memo values (a deposit tag can identify the recipient's exchange account).

The yaob bridge-crossing proof test covers descriptor-only construction, plugin-faithful reads, memo round-trip via getMemos, and the synthetic surviving the wire format back to the GUI.

Testing: tsc clean, 166 mocha tests pass (3 new), eslint clean. In-app verification (linked into edge-react-gui with the Stealth Send UI): a real cross-chain send-to-address executed on the iOS sim through this mechanism (Base ETH to an Ethereum address via ChangeNOW, deposit broadcast on-chain, swap success scene reached).

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Note

Medium Risk
Touches the central swap quote path and public API types (EdgeSwapRequest, swap tx metadata); plugins unchanged but GUI consumers assuming payoutWalletId is always set need updates.

Overview
Enables swap-to-address (private send / send-to-any-asset) by letting EdgeSwapRequest specify either toWallet or a new toAddressInfo descriptor (toPluginId, toAddress, optional toMemos). The core validates exactly one destination, then resolveSwapRequest in fetchSwapQuotes builds a bridgified synthetic EdgeCurrencyWallet from real currencyConfig so existing swap plugins still see a normal toWallet (addresses/receive address return the pasted destination; optional getMemos on EdgeSyntheticDestinationWallet for tags).

payoutWalletId on EdgeTxActionSwap and EdgeTxSwap is now optional when there is no payout wallet; payoutAddress holds the destination. Disk cleaners and SwapCurrencyError were updated for optional toWallet / toAddressInfo. Swap quote logging redacts pasted addresses and memo values.

New tests cover synthetic wallet behavior across the yaob bridge.

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[j0ntz]

📸 Test evidence (in-app swap-to-address via synthetic destination)

agent proof 1216251688512498 03 send to any quote

agent proof 1216251688512498 04 send to any success

Captured by the agent's in-app test run (build-and-test).

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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