Return timestamp when last sync was launched

[ZIMkaRU]

This PR adds ability to return the timestamp when the last sync was launched to add this info to the layouts of the new design

---

Basic changes:

• Implements dao getLastFinishedSyncQueueJob method
• Returns mts when last sync was launched in response payload of signIn method
• Adds test cases for lastSyncMts field

---

Request example:

{
  "method": "signIn",
  "auth": {
    "email": "[email protected]",
    "isSubAccount": false
  }
}

Response example:

{
  "jsonrpc": "2.0",
  "result": {
    "email": "[email protected]",
    "isSubAccount": false,
    "token": "e4afe3e3-1c96-450d-b8ec-5a604f664893",
    "shouldNotSyncOnStartupAfterUpdate": false,
    "authTokenTTLSec": null,
    "localUsername": null,
    "lastSyncMts": 1686902405802 // added field
  },
  "id": null
}

[ezewer]

looks good to me!