Add draft- prefix to ERC-7821 (#5742)

Author: ernestognw

contracts/account/extensions/ERC7821.sol renamed to contracts/account/extensions/draft-ERC7821.sol

@@ -3,7 +3,7 @@
 pragma solidity ^0.8.20;
 
 import {ERC7579Utils, Mode, CallType, ExecType, ModeSelector} from "../utils/draft-ERC7579Utils.sol";
-import {IERC7821} from "../../interfaces/IERC7821.sol";
+import {IERC7821} from "../../interfaces/draft-IERC7821.sol";
 import {Account} from "../Account.sol";
 
 /**

contracts/interfaces/IERC7821.sol renamed to contracts/interfaces/draft-IERC7821.sol

@@ -9,7 +9,7 @@ import {ERC721Holder} from "../../token/ERC721/utils/ERC721Holder.sol";
 import {ERC1155Holder} from "../../token/ERC1155/utils/ERC1155Holder.sol";
 import {ERC4337Utils} from "../../account/utils/draft-ERC4337Utils.sol";
 import {ERC7739} from "../../utils/cryptography/signers/draft-ERC7739.sol";
-import {ERC7821} from "../../account/extensions/ERC7821.sol";
+import {ERC7821} from "../../account/extensions/draft-ERC7821.sol";
 import {MODULE_TYPE_VALIDATOR} from "../../interfaces/draft-IERC7579.sol";
 import {PackedUserOperation} from "../../interfaces/draft-IERC4337.sol";
 import {AbstractSigner} from "../../utils/cryptography/signers/AbstractSigner.sol";

contracts/mocks/account/AccountMock.sol

@@ -9,7 +9,7 @@ import {ERC7579Utils, Execution, Mode, ModeSelector, ModePayload} from "@openzep
 import {ERC4337Utils, IEntryPointExtra} from "@openzeppelin/contracts/account/utils/draft-ERC4337Utils.sol";
 import {Strings} from "@openzeppelin/contracts/utils/Strings.sol";
 import {PackedUserOperation} from "@openzeppelin/contracts/interfaces/draft-IERC4337.sol";
-import {ERC7821} from "@openzeppelin/contracts/account/extensions/ERC7821.sol";
+import {ERC7821} from "@openzeppelin/contracts/account/extensions/draft-ERC7821.sol";
 
 contract AccountERC7702MockConstructor is AccountERC7702Mock {
     constructor() EIP712("MyAccount", "1") {}