feat(keyring-api): add stake:{deposit,withdraw} transaction types (#394)

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<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adds `stake:deposit` and `stake:withdraw` to `TransactionType` and
permits them in `TransactionStruct.type`.
> 
> - **API**:
> - **Transaction types**: Add `TransactionType.StakeDeposit`
(`stake:deposit`) and `TransactionType.StakeWithdraw`
(`stake:withdraw`).
> - **Schema**: Include the new types in `TransactionStruct.type` enum.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
0bea09a. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: aganglada

packages/keyring-api/src/api/transaction.ts

@@ -155,6 +155,15 @@ export enum TransactionType {
    */
   BridgeReceive = 'bridge:receive',
 
+  /**
+   * Represents a stake deposit transaction.
+   */
+  StakeDeposit = 'stake:deposit',
+
+  /**
+   * Represents a stake withdrawal transaction.
+   */
+  StakeWithdraw = 'stake:withdraw',
   /**
    * The transaction type is unknown. It's not possible to determine the
    * transaction type based on the information available.
@@ -282,6 +291,8 @@ export const TransactionStruct = object({
     `${TransactionType.Swap}`,
     `${TransactionType.BridgeSend}`,
     `${TransactionType.BridgeReceive}`,
+    `${TransactionType.StakeDeposit}`,
+    `${TransactionType.StakeWithdraw}`,
     `${TransactionType.Unknown}`,
   ]),