enhance(backend): Replace bcrypt with Argon2

Squashed commit of the following:

commit 4862fd8467d529c54d0aa3e6abff15a574459a8b
Author: Shun Sakai <sorairolake@protonmail.ch>
Date:   Wed Oct 23 20:44:30 2024 +0900

    chore(backend): Update `argon2` package

commit a52eff5deaee39c0a70c83da49ca58d0eab8d513
Author: NoriDev <m1nthing2322@gmail.com>
Date:   Mon Oct 7 18:11:34 2024 +0900

    Revert "tweak 0dc322b6 (1673beta/cherrypick#88)"

    This reverts commit ab6a5d0c3dbe7146de19d72d08658b1c011fe30a.

commit be51daec8a916a2668ea5794e067bde06499e1a4
Author: Mar0xy <marie@kaifa.ch>
Date:   Wed Sep 27 21:46:56 2023 +0200

    upd: rehash misskey passwords with argon2 on login

commit 67b124b7e6e8f1b1d1738ea9a123ab0500876d58
Author: Mar0xy <marie@kaifa.ch>
Date:   Fri Sep 22 00:21:57 2023 +0200

    upd: swap bcrypt to argon2

packages/backend/src/server/api/endpoints/i/2fa/update-key.ts

@@ -3,7 +3,6 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-import bcrypt from 'bcryptjs';
 import { Inject, Injectable } from '@nestjs/common';
 import { Endpoint } from '@/server/api/endpoint-base.js';
 import type { UserSecurityKeysRepository } from '@/models/_.js';