[bmc08gt]

Syncs transaction.v1 to ocp-protobuf-api@98cf14de (#71), for release as 0.9.0.

The server side is code-payments/ocp-server#278. It builds CoinbaseStableSwapper's swap_v2 instruction when the client asks for it. swap_v2 is swap without the deprecated whitelist account.

Contract diff

• swap_version (uint32, lte = 2) is added to the CoinbaseStableSwapper initiate params of StatefulSwapRequest (field 9) and StatelessSwapRequest (field 4). Only 2 selects swap_v2. Unset, 0 and 1 keep the legacy swap.
• Comments only: the swap step in both responses' CoinbaseStableSwapper server parameters is now listed as Swap or SwapV2, per swap_version.
• Nothing was renumbered or removed.

The CHANGELOG.md entry for 0.9.0 is in this PR, so publish.yml can run once it merges.

App PRs

Both are drafts until 0.9.0 is published and their pins move:

• Android: feat(opencode): build CoinbaseStableSwapper SwapV2 for stablecoin swaps code-android-app#1817
• iOS: feat(swap): build Coinbase SwapV2 and request swap_version 2 code-ios-app#1104

Neither app should ship v2 before code-payments/ocp-server#278 is deployed. An older server ignores swap_version and builds swap, the app signs swap_v2, and the swap fails.