fix(sdk-coin-trx): emit canonical AccountCreate raw_data_hex

AccountCreateContract's enum value is 0 — the proto3 default for the
outer Transaction.Contract.type field. The SDK's protobuf encoder
included this default-valued tag in the wire format (2-byte `0800`
inside the contract envelope), but TRON's node re-serializes raw_data
from broadcast JSON following strict proto3 semantics and omits
default-valued fields. The canonical raw_data_hex is therefore 2 bytes
shorter, with a different sha256 (txID).

For TSS wallets this manifested as a SIGERROR on broadcast:

  Validate signature error: <sig> is signed by <random T...> but it is
  not contained of permission

The TSS signature was valid for sha256(SDK_raw_data_hex), but TRON
validated it against sha256(canonical_raw_data_hex). With a mismatched
digest, ECDSA recovery returns an unrelated pubkey whose TRON address
is not in the wallet's permission set. Hot-wallet flows didn't trip
this because they sign-then-recover locally against the same buggy
bytes the SDK emits.

Other contract builders (Transfer=1, FreezeBalanceV2=11, VoteWitness=4,
DelegateResource=57, ...) all have non-default enum values, so their
SDK output matches TRON's canonical encoding by accident. AccountCreate
was uniquely affected. See the analogous proto3-default guard already
present in freezeBalanceTxBuilder.ts for the inner `resource: BANDWIDTH=0`
field.

Fix: drop the explicit `type` field from the txContract object in
getAccountCreateTxRawDataHex so the encoder omits it, matching the
canonical wire format TRON computes from the broadcast JSON. Includes
a regression test that asserts raw_data_hex does not include the
proto3-default tag and uses the canonical contract framing.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: bhavidhingra

modules/sdk-coin-trx/src/lib/accountCreateTxBuilder.ts

@@ -15,8 +15,6 @@ import {
 } from './utils';
 import { ACCOUNT_CREATE_TYPE_URL } from './constants';
 
-import ContractType = protocol.Transaction.Contract.ContractType;
-
 export class AccountCreateTxBuilder extends TransactionBuilder {
   protected _signingKeys: BaseKey[];
   // Stored as hex address, consistent with _ownerAddress
@@ -148,8 +146,13 @@ export class AccountCreateTxBuilder extends TransactionBuilder {
     };
     const accountCreateContract = protocol.AccountCreateContract.fromObject(rawContract);
     const accountCreateContractBytes = protocol.AccountCreateContract.encode(accountCreateContract).finish();
+    // AccountCreateContract is enum value 0 — the proto3 default. TRON's node
+    // re-serializes raw_data from broadcast JSON and omits default-valued
+    // fields, producing a different raw_data_hex (and txID) than the SDK if
+    // we encode the type field explicitly. Skip it so signing and broadcast
+    // hashes match. See freezeBalanceTxBuilder.ts:175-181 for the same class
+    // of issue on the inner `resource` field.
     const txContract = {
-      type: ContractType.AccountCreateContract,
       parameter: {
         value: accountCreateContractBytes,
         type_url: ACCOUNT_CREATE_TYPE_URL,

modules/sdk-coin-trx/test/unit/transactionBuilder/accountCreateTxBuilder.ts

@@ -115,6 +115,38 @@ describe('Tron AccountCreate builder', function () {
 
       assert.equal(tx2.toJson().txID, originalTxId);
     });
+
+    // Regression test: AccountCreateContract's enum value is 0, which is the
+    // proto3 default for the outer Transaction.Contract.type field. When the
+    // SDK explicitly encoded `type: 0`, the wire format included the 2-byte
+    // tag `0800` inside the contract envelope. TRON's node re-serializes
+    // raw_data from broadcast JSON and omits default-valued fields, producing
+    // a 2-byte-shorter canonical raw_data_hex and a different txID. The TSS
+    // signature was valid for the SDK's hash but recovered to a garbage
+    // pubkey under TRON's canonical hash, so AccountCreate broadcasts failed
+    // with SIGERROR "signed by <random T...> but not contained of permission".
+    it('produces raw_data_hex without the proto3 default-valued type field', async () => {
+      const timestamp = 1779455020653;
+      const expiration = 1779465820653;
+      const txBuilder = initTxBuilder();
+      txBuilder.timestamp(timestamp);
+      txBuilder.expiration(expiration);
+      const tx = await txBuilder.build();
+      const rawDataHex = tx.toJson().raw_data_hex;
+
+      // The buggy encoding had `5a68 0800 1264` (contract tag, length 0x68,
+      // type=0, parameter tag, length 0x64). The canonical encoding TRON
+      // re-serializes to drops the `0800` and decrements the contract length
+      // by 2 -> `5a66 1264`.
+      assert.ok(
+        !rawDataHex.includes('5a68080012'),
+        `raw_data_hex must not include the proto3-default \`type: 0\` tag (0800). Got: ${rawDataHex}`
+      );
+      assert.ok(
+        rawDataHex.includes('5a661264'),
+        `raw_data_hex must use the canonical contract framing (5a66...1264). Got: ${rawDataHex}`
+      );
+    });
   });
 
   describe('should validate', () => {