Retrieving model with uuid and alias gives different results

There are a few minor differences in "description" and "format" (null vs []). The main difference is that the parameters field of the model instance is empty when the model is retrieved via alias.

https://validation.brainsimulation.eu/models/32dc30ba-3de3-4c75-83f7-5c930de346d7

{
  "id": "32dc30ba-3de3-4c75-83f7-5c930de346d7",
  "uri": "https://kg.ebrains.eu/api/instances/32dc30ba-3de3-4c75-83f7-5c930de346d7",
  "name": "Reduced striatum microcircuit",
  "alias": "striatum_microcircuit_test",
  "author": [
     ...cut to save space...
  ],
  "owner": [
    {
      "given_name": "Andrew P.",
      "family_name": "Davison",
      "orcid": "https://orcid.org/0000-0002-4793-7541"
    }
  ],
  "project_id": "basal-ganglia-validation",
  "organization": null,
  "private": true,
  "cell_type": null,
  "model_scope": "network: microcircuit",
  "abstraction_level": "spiking neurons: biophysical",
  "brain_region": "striatum",
  "species": "Mus musculus",
  "description": "This is a small-scale model of the striatum microcircuit, used only for testing the EBRAINS Model Validation Framework",
  "date_created": "2023-06-06",
  "format": null,
  "images": null,
  "old_uuid": null,
  "instances": [
    {
      "id": "82f5a109-7fbc-4070-82b9-155d118ac462",
      "uri": "https://kg.ebrains.eu/api/instances/82f5a109-7fbc-4070-82b9-155d118ac462",
      "version": "20230606",
      "description": "",
      "parameters": "https://data-proxy.ebrains.eu/api/v1/buckets/basal-ganglia-validation/model_parameters/striatum_microcircuit_20230606.json",
      "code_format": null,
      "source": "https://github.com/apdavison/basalunit",
      "license": "The 3-Clause BSD License",
      "hash": null,
      "timestamp": "2023-06-06",
      "morphology": null,
      "model_id": "32dc30ba-3de3-4c75-83f7-5c930de346d7",
      "alternatives": []
    }
  ]
}

https://validation.brainsimulation.eu/models/striatum_microcircuit_test

{
  "id": "32dc30ba-3de3-4c75-83f7-5c930de346d7",
  "uri": "https://kg.ebrains.eu/api/instances/32dc30ba-3de3-4c75-83f7-5c930de346d7",
  "name": "Reduced striatum microcircuit",
  "alias": "striatum_microcircuit_test",
  "author": [
      ...cut to save space...
  ],
  "owner": [
    {
      "given_name": "Andrew P.",
      "family_name": "Davison",
      "orcid": "https://orcid.org/0000-0002-4793-7541"
    }
  ],
  "project_id": "basal-ganglia-validation",
  "organization": null,
  "private": true,
  "cell_type": null,
  "model_scope": "network: microcircuit",
  "abstraction_level": "spiking neurons: biophysical",
  "brain_region": "striatum",
  "species": "Mus musculus",
  "description": "This is a small-scale model of the striatum microcircuit, used only for testing the EBRAINS Model Validation Framework",
  "date_created": "2023-06-06",
  "format": [],
  "images": null,
  "old_uuid": null,
  "instances": [
    {
      "id": "82f5a109-7fbc-4070-82b9-155d118ac462",
      "uri": "https://kg.ebrains.eu/api/instances/82f5a109-7fbc-4070-82b9-155d118ac462",
      "version": "20230606",
      "description": null,
      "parameters": null,
      "code_format": null,
      "source": "https://github.com/apdavison/basalunit",
      "license": "The 3-Clause BSD License",
      "hash": null,
      "timestamp": "2023-06-06",
      "morphology": null,
      "model_id": "32dc30ba-3de3-4c75-83f7-5c930de346d7",
      "alternatives": []
    }
  ]
}

Context:

{
  "version": "3beta",
  "datastore": "core.kg.ebrains.eu",
  "build": {
    "git": "8d916b33",
    "target": "production",
    "date": "2023-05-12T11:22:56+02:00"
  }
}

Start by reproducing the responses from the UUID and alias model URLs shown in the issue, then trace the API entry points that retrieve models by each identifier. Compare how description, format, and instance parameters are populated; done means both routes return equivalent model data, with tests covering the two retrieval paths.