Support Verifiable Credential file uploading

[CJGutz]

Is your feature request related to a problem?

Users might have a verifiable credential stored as a file on their computer or phone.
They should not need to open up their file, copy it, and then paste it in.

Describe the solution you would like

Create a small button below the input field to support uploading. It should open the computers default file explorer. Any file can be selected. When selected. The input field is minimized as usual to show the analyzed data.

Acceptance Criteria

Any device is supported.