api: return minimal info form the `GET /v1/app/{id}/bricks` endpoint

[dido18]

Describe the problem

If confirmed by the AppLab that the variables and config_variables are not used, we can remove some info from the list of bricks installed into the app.

To reproduce

curl http://localhost:8800/v1/apps/ZXhhbXBsZXM6aW1hZ2UtY2xhc3NpZmljYXRpb24/bricks 

{
  "bricks": [
    {
      "id": "arduino:image_classification",
      "name": "Image Classification",
      "author": "Arduino",
      "category": "video",
      "status": "installed",
      "variables": {
        "CUSTOM_MODEL_PATH": "/home/arduino/.arduino-bricks/ei-models",
        "EI_CLASSIFICATION_MODEL": "/models/ootb/ei/mobilenet-v2-224px.eim"
      },
      "config_variables": [
        {
          "name": "CUSTOM_MODEL_PATH",
          "value": "/home/arduino/.arduino-bricks/ei-models",
          "description": "path to the custom model directory",
          "required": false
        },
        {
          "name": "EI_CLASSIFICATION_MODEL",
          "value": "/models/ootb/ei/mobilenet-v2-224px.eim",
          "description": "path to the model file",
          "required": false
        }
      ]
    }
  ]
}

Expected behavior

curl http://localhost:8800/v1/apps/ZXhhbXBsZXM6aW1hZ2UtY2xhc3NpZmljYXRpb24/bricks 

{
  "bricks": [
    {
      "id": "arduino:image_classification",
      "name": "Image Classification",
      "author": "Arduino",
      "category": "video",
      "status": "installed",
  ]
}

Arduino App CLI version

0.6.8

Additional context

The list brick endpoint returns the sma minila info

curl 127.0.0.1:8800/v1/bricks 
{
  "bricks": [
    {
      "id": "arduino:dbstorage_sqlstore",
      "name": "Database - SQL",
      "author": "Arduino",
      "description": "Simplified database storage layer for Arduino sensor data using SQLite local database.",
      "category": "storage",
      "status": "installed",
      "require_model": false
    }
]

Issue checklist

• I searched for previous reports in the issue tracker
• I verified the problem still occurs when using the latest version
• My report contains all necessary details

[mirkoCrobu]

Assuming the Figma flow has remained unchanged, the config_variables fields were explicitly asked by the IDE team:
#18

[dido18]

This issue can be closed since it is used by AppLab.

Before starting an app, the ApLab checks if there are any bricks with mandatory variables or models that haven’t been set. To do this, the list of bricks is called directly to do a single call.