Trufos Importer

**Is your feature request related to a problem? Please describe.**
#622 introduces a Trufos exporter. This is the matching import feature.

**Describe the solution you'd like**
- Add UI part to import Trufos Collection from ZIP (other import types already implemented in UI, just enable the Trufos import tab)
- Implement `TrufosImporter` that reads a ZIP file (stream based if possible) and unzips it to the directory selected by the user
- If any `.secret.json.bin` are in the ZIP, the should be encrypted during unzip (they should be in plaintext from exported ZIPs, if not, ignore them)

**Describe alternatives you've considered**

**Additional context**
- See #622