refactor(sdk): run the KeyWallet helpers on platform-wallet-ffi

`TransactionDecoder.decode`, `Mnemonic.generate`, `Mnemonic.validate`, `KeyDerivation.getIdentityAuthenticationPath` and `Address.validate` keep their Swift signatures and now call `platform-wallet-ffi`. The Kotlin JNI `decodeTransaction` and `generateMnemonic` bridges do the same and map failures through `take_pwffi_error`, so `rs-unified-sdk-jni` no longer depends on `key-wallet-ffi`.

`platform_wallet_mnemonic_word_list` takes its language as a plain integer too, and the Swift callers pass `MnemonicLanguage.rawValue`. The JNI bridge passes Kotlin's ordinal through unchanged, so an unknown ordinal is an error instead of English, and Kotlin's `Language` gains Japanese, Korean, Portuguese and Spanish.

New Swift API lets apps stop rebuilding a `KeyWallet` wallet from the phrase: `Mnemonic.walletId(for:network:)`, `Mnemonic.firstReceiveAddress(for:network:)`, and `ManagedPlatformWallet.findBIP44AddressPath(address:)` and `bip44AddressPrivateKey(address:storage:)` for the BIP-44 account scan. The last shares `coreAddressPrivateKey`'s resolver handling. Every helper that passes a string to C rejects an embedded NUL. Parity tests pin the wallet id and the first receive address against the `KeyWallet` code they replace, for English and French phrases.

`Mnemonic.generate`, `TransactionDecoder.decode` and `getIdentityAuthenticationPath` now throw `PlatformWalletError`. The other `KeyWallet` classes and `rs-unified-sdk-ffi`'s `key-wallet-ffi` dependency are unchanged.

Author: xdustinface

Cargo.lock

@@ -163,8 +163,8 @@ schema-hash crash at app start on devices with old data.
 
 ## Architecture Notes
 
-- One JNI library: `rs-unified-sdk-jni` links `rs-sdk-ffi`,
-  `platform-wallet-ffi`, and `key-wallet-ffi` as **rlibs** — FFI structs
+- One JNI library: `rs-unified-sdk-jni` links `rs-sdk-ffi` and
+  `platform-wallet-ffi` as **rlibs** — FFI structs
   never cross JNI by value. Errors become
   `org.dashfoundation.dashsdk.ffi.DashSDKException(code, message)`;
   every export is panic-guarded.

packages/kotlin-sdk/BUILD_GUIDE_FOR_AI.md

@@ -10,7 +10,7 @@ file too; the architectural rules are identical.
    response to Rust state (via the persistence callback bridge).
 2. **Load data** — expose Room `Flow` queries for reactive UI updates.
 3. **Bridge** — thin JNI wrappers around functions defined in the Rust
-   libraries (`rs-sdk-ffi`, `platform-wallet-ffi`, `key-wallet-ffi`).
+   libraries (`rs-sdk-ffi`, `platform-wallet-ffi`).
 
 ## Forbidden in Kotlin (belongs in Rust `platform-wallet`)
 

packages/kotlin-sdk/CLAUDE.md

@@ -20,7 +20,7 @@ kotlin-sdk/
 ```
 
 The native layer is [`packages/rs-unified-sdk-jni`](../rs-unified-sdk-jni), a Rust JNI shim
-over `rs-sdk-ffi`, `platform-wallet-ffi` and `key-wallet-ffi`. There is no C
+over `rs-sdk-ffi` and `platform-wallet-ffi`. There is no C
 glue and no generated headers on Android — the shim calls the FFI crates as
 ordinary Rust dependencies and exposes JNI symbols directly.
 

packages/kotlin-sdk/README.md

@@ -2,7 +2,7 @@
 # Build libdash_sdk_jni.so for Android — the analog of ../swift-sdk/build_ios.sh.
 #
 # Produces one cdylib per ABI containing the JNI exports of rs-unified-sdk-jni plus
-# the C ABI of rs-sdk-ffi / platform-wallet-ffi / key-wallet-ffi (linked in
+# the C ABI of rs-sdk-ffi / platform-wallet-ffi (linked in
 # as rlibs), and drops them into sdk/src/main/jniLibs/<abi>/ where AGP
 # packages them.
 #

packages/kotlin-sdk/build_android.sh

@@ -16,8 +16,8 @@ internal object MnemonicNative {
     external fun destroyResolver(handle: Long)
 
     /**
-     * Generate a BIP-39 mnemonic (key-wallet-ffi). wordCount ∈ {12,15,18,21,24};
-     * language is the FFILanguage ordinal (0 = English).
+     * Generate a BIP-39 mnemonic (platform-wallet-ffi). wordCount ∈ {12,15,18,21,24};
+     * language is the FFIMnemonicLanguage ordinal (0 = English).
      * @throws DashSDKException on failure
      */
     external fun generateMnemonic(wordCount: Int, language: Int): String

packages/kotlin-sdk/sdk/src/main/kotlin/org/dashfoundation/dashsdk/ffi/MnemonicNative.kt

@@ -7,8 +7,8 @@ package org.dashfoundation.dashsdk.ffi
 internal object TxDecodeNative {
 
     /**
-     * Consensus-decode raw transaction bytes (key-wallet-ffi
-     * `transaction_decode`) into the packed big-endian BLOB documented in
+     * Consensus-decode raw transaction bytes (platform-wallet-ffi
+     * `platform_wallet_transaction_decode`) into the packed big-endian BLOB documented in
      * `tx_decode.rs` / parsed by
      * [org.dashfoundation.dashsdk.keywallet.TransactionDecoder.parseBlob].
      * [networkOrd] is [org.dashfoundation.dashsdk.Network.ffiValue].

packages/kotlin-sdk/sdk/src/main/kotlin/org/dashfoundation/dashsdk/ffi/TxDecodeNative.kt

@@ -6,19 +6,23 @@ import org.dashfoundation.dashsdk.ffi.MnemonicNative
 
 /**
  * BIP-39 mnemonic operations — port of `SwiftDashSDK/KeyWallet/Mnemonic.swift`.
- * Generation runs entirely in Rust (key-wallet-ffi); the phrase transits
+ * Generation runs entirely in Rust (platform-wallet-ffi); the phrase transits
  * Kotlin only to be shown for backup and stored encrypted.
  */
 object Mnemonic {
 
-    /** Mirror of the iOS `MnemonicLanguage` enum (FFILanguage ordinals). */
+    /** Mirror of the iOS `MnemonicLanguage` enum (FFIMnemonicLanguage ordinals). */
     enum class Language(val ffiValue: Int) {
         ENGLISH(0),
         CHINESE_SIMPLIFIED(1),
         CHINESE_TRADITIONAL(2),
         CZECH(3),
         FRENCH(4),
         ITALIAN(5),
+        JAPANESE(6),
+        KOREAN(7),
+        PORTUGUESE(8),
+        SPANISH(9),
     }
 
     /**

packages/kotlin-sdk/sdk/src/main/kotlin/org/dashfoundation/dashsdk/keywallet/Mnemonic.kt

@@ -10,7 +10,7 @@ import org.dashfoundation.dashsdk.ffi.TxDecodeNative
  * A consensus-decoded Dash transaction: per-output `(address, value,
  * script)` plus per-input previous outpoints with a best-effort P2PKH
  * sender address — port of `SwiftDashSDK/KeyWallet/TransactionDecoder.swift`
- * (platform PR #3981) over key-wallet-ffi's `transaction_decode`.
+ * (platform PR #3981) over platform-wallet-ffi's `platform_wallet_transaction_decode`.
  *
  * Wallet persistence stores every transaction's raw bytes
  * (`TransactionEntity.transactionData`) but only materializes TXO rows for
@@ -88,8 +88,8 @@ class DecodedTransaction(
 }
 
 /**
- * Pure utility — decodes raw transaction bytes via key-wallet-ffi's
- * `transaction_decode`. No wallet handle or state involved.
+ * Pure utility — decodes raw transaction bytes via platform-wallet-ffi's
+ * `platform_wallet_transaction_decode`. No wallet handle or state involved.
  */
 object TransactionDecoder {
 
@@ -99,7 +99,7 @@ object TransactionDecoder {
      * @param txData serialized transaction bytes (e.g. a persisted
      *   `TransactionEntity.transactionData`).
      * @param network network used to render addresses (base58 version bytes).
-     * @throws org.dashfoundation.dashsdk.errors.DashSdkError.InvalidParameter
+     * @throws org.dashfoundation.dashsdk.errors.DashSdkError.PlatformWallet
      *   for malformed or empty bytes (including trailing garbage).
      */
     fun decode(txData: ByteArray, network: Network): DecodedTransaction {

packages/kotlin-sdk/sdk/src/main/kotlin/org/dashfoundation/dashsdk/keywallet/TransactionDecoder.kt

@@ -134,8 +134,8 @@ class PlatformWalletPersistenceHandler(
     /**
      * Where the sweep pass gets a stored loser's input outpoints (the
      * outpoint-keyed hold, see `applySweptTransactions`). The production
-     * default decodes the stored consensus bytes through key-wallet-ffi's
-     * `transaction_decode`; tests inject a fake keyed by txid, since the
+     * default decodes the stored consensus bytes through platform-wallet-ffi's
+     * `platform_wallet_transaction_decode`; tests inject a fake keyed by txid, since the
      * native library is not loadable under Robolectric.
      */
     private val storedTransactionInputs: StoredTransactionInputs =
@@ -4265,8 +4265,8 @@ fun interface StoredTransactionInputs {
 }
 
 /**
- * Production [StoredTransactionInputs]: key-wallet-ffi's
- * `transaction_decode` through [org.dashfoundation.dashsdk.keywallet.TransactionDecoder].
+ * Production [StoredTransactionInputs]: platform-wallet-ffi's
+ * `platform_wallet_transaction_decode` through [org.dashfoundation.dashsdk.keywallet.TransactionDecoder].
  * The decoder is a stateless marshaler — it takes no wallet-manager lock —
  * so calling it from inside a persistence callback (which runs while Rust
  * holds that lock) cannot deadlock; the "no native calls under