As a user I want to backup my identity with a PDF file (QR code included)

[satazor]

Story

As a user I want to backup my identity using a PDF.

Description

At the moment we just support mnemonics, but we must also generate an importable PDF, with a QR code, the mnemonic, and some other information such as the DID.

Tasks

• [x] #26 (backup predict under the create user journey)
• [x] #173 (placeholder implementation)
• [ ] #224

Acceptance Criteria

• [ ] Generate a PDF file with the IDM "brand" (not nomios), with the mnemonic, the QR code and the DID.