W-21920947: Adopt new backend response, table output, and structured errors

[ukanoja-sf]

What does this PR do?

Adopt new backend response, table output, and structured errors

What issues does this PR fix or reference?

GUS: @W-21920947@

Local Results

Single license success

Single license validation failure

Multiple licenses success

{
  "licenses": [
    {
      "namespacePrefix": "demo1",
      "permissionSetLicense": "premium",
      "quantity": 50,
      "startDate": "2026-04-07",
      "endDate": "2027-03-20"
    },
    {
      "namespacePrefix": "demo1",
      "permissionSetLicense": "starter",
      "quantity": 10,
      "startDate": "2026-04-07",
      "endDate": "2027-03-20"
    }
  ]
}

Multiple licenses multiple validations failures

{
  "licenses": [
    {
      "namespacePrefix": "demo1",
      "permissionSetLicense": "premium",
      "quantity": 50,
      "startDate": "2026-04-07-02",
      "endDate": "2027-03-20-03"
    },
    {
      "namespacePrefix": "demo420",
      "permissionSetLicense": "starter",
      "quantity": 10,
      "startDate": "2026-04-07",
      "endDate": "2027-03-20-3"
    }
  ]
}