[bmc08gt]

Syncs the contract to flipcash2-protobuf-api@6de4f9ad (upstream #160, #161, #162, #163) and adds the 0.23.0 changelog entry. Release as 0.23.0.

This upgrade breaks source in Swift only. boosted_reaction on both activity crypto notification metadata messages moved into a new oneof context, so hasBoostedReaction is gone, and MetadataUpdate.kind gained a case that exhaustive switches must handle. Field numbers are unchanged, so the wire format is not affected.

Contract changes

• Editable rules: EditChatRequest.rules (field 6) edits a public group's listener and speaker minimum balances. MetadataUpdate.RulesChanged (oneof field 8) announces the edit.
• Payment request updates: ChatUpdate.payment_request_updates (field 10), a PaymentRequestUpdateBatch of PaymentRequestUpdate: created, or Updates at a version made of SharePaymentUpdate and StatusUpdate.
• Feed links: activity.v1.RequestedPayment as requested_payment (oneof field 4) on DirectlySentCryptoNotificationMetadata and ReceivedCryptoNotificationMetadata.
• Test push: push.v1.Push.SendTestPush.
• Appended enum cases: EditChatResponse.Result INVALID_RULES = 7 and RULES_NOT_SATISFIED = 8. Nothing was renumbered.

App PRs

Both are drafts. They contain only the scaffolding and stay blocked until 0.23.0 is published and their pins move. Neither applies payment request updates to UI state yet, and iOS does not persist requestedPayment.

• Android: feat(flipcash): scaffold flipcash2 0.23.0 contract code-android-app#1876
• iOS: feat(chat): scaffold flipcash2 0.23.0 contract code-ios-app#1157