Update public-forms prefilled logic

[Abhinegi2]

The current implementation of prefilled values needs to be updated to a new (because a lot of irrelevant, duplicate config), more structured format in both how it’s saved in the DB and how it’s handled in the UI components.
Current config/structure:

  "prefilledFields": [
    {
      "id": "projectStatus",
      "defaultValue": {
        "mode": "static",
        "config": {
          "value": "NEU"
        }
      },
      "hideFromForm": true
    }
  ],

Suggested Changes:

1. Update EditPrefilledValuesComponent

• Modify it to save prefilled in the new format:

  "prefilled": {
    "projectStatus": {
      "mode": "static",
      "config": {
        "value": "NEU"
      }
    }
  }
  

2. Update PublicFormComponent

• Refactor the handlePrefilledFields method to work with the new format.

3. Add Migration

• Implement a migration method in PublicFormComponent to ensure backward compatibility with existing data.