curl --request POST \
  --url https://api.wacht.dev/auth/signup \
  --header 'Content-Type: application/x-www-form-urlencoded' \
  --data email=john@example.com \
  --data first_name=John \
  --data last_name=Doe \
  --data username=johndoe \
  --data 'phone_number=+1234567890' \
  --data 'phone_country_code=+1' \
  --data 'password=SecurePass123!'

{
  "id": "123456789012345678",
  "created_at": "2024-01-15T10:30:00Z",
  "updated_at": "2024-01-15T10:30:00Z",
  "signin_attempts": [
    {
      "id": "<string>",
      "created_at": "2023-11-07T05:31:56Z",
      "updated_at": "2023-11-07T05:31:56Z"
    }
  ],
  "signins": [
    {
      "id": "<string>",
      "created_at": "2023-11-07T05:31:56Z",
      "updated_at": "2023-11-07T05:31:56Z"
    }
  ],
  "signup_attempts": [
    {
      "id": "<string>",
      "created_at": "2023-11-07T05:31:56Z",
      "updated_at": "2023-11-07T05:31:56Z"
    }
  ],
  "active_signin_id": "987654321098765432",
  "active_signin": {
    "id": "<string>",
    "created_at": "2023-11-07T05:31:56Z",
    "updated_at": "2023-11-07T05:31:56Z"
  }
}