Improve vault encryption

[gantunesr]

Description

As part of the new KeyringController API, there's a need to improve the current encryption logic for the vault.

Today the user's password directly encrypts the vault, there's an improvement opportunity where the KeyringController can use an encryption key to encrypt the vault. Next is presented the specific steps for two use cases,

Use Case: Lock the vault

1. Create or get encryption-key
2. Encrypt vault with encryption-key
3. Encrypt encryption-key with password

Use Case: Unlock the vault

1. Decrypt encryption-key with password
2. Decrypt vault with encryption-key

Acceptance Criteria

• [ ] The encryption key must have a defined use policy
• [ ] All new code must have tests
• [ ] All new code must be document

Reference

• API Re-design Proposal

[gantunesr]

Encrypted Vault Example

{
  cipher: "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",
  iv: "fd98fce552738df2a183da14acc9b8e2",
  salt: "/w1IHCoSZrPcUZMlLzq0qw==",
  lib: "original"
}

Decrypted Vault Example

[
  // HD Keyring
  {
    data: {
      hdPath: "m/44'/60'/0'/0",
      mnemonic: [110, 111, 98, 108, 101, 32, 99, 114, 117, 105, 115, 101, 32, 114, 105, 99, 104, 32, 112, 117, 98, 108, 105, 99, 32, 112, 114, 105, 115, 111, 110, 32, 115, 101, 109, 105, 110, 97, 114, 32, 102, 101, 119, 32, 115, 101, 99, 111, 110, 100, 32, 115, 116, 101, 101, 108, 32, 97, 120, 105, 115, 32, 99, 114, 97, 102, 116, 32, 115, 117, 114, 102, 97, 99, 101],
      numberOfAccounts: 1
    },
    type: "HD Key Tree"
  },
  // Simple Keyring
  {
    data: ["08dbe017e1fd5ddb709de0456ba602b630025449dc8313ebab22d624e5208a69"],
    type: "Simple Key Pair"
  },
  // QR Keyring
  {
    data: {
      accounts: [],
      childrenPath: "0/*",
      currentAccount: 0,
      hdPath: "",
      indexes: {},
      initialized: false,
      keyringAccount: "account.standard",
      keyringMode: "hd",
      name: "QR Hardware",
      page: 0,
      paths: {},
      perPage: 5,
      version: 1,
      xfp: "",
      xpub: "",
    },
    type: "QR Hardware Wallet Device"
  }
]