[BUG] SFTP cannot handle username with @ symbol

[slapcat]

Description

My username is an email address with an @ symbol and nearly all functionality with SFTP breaks with that (adding SSH key, removing key, connecting with key). The same server works fine with a username without an @.

Steps to reproduce

This issue affects multiple components of termscp:

1. Add SSH key with hostname server.com and user [email protected].
2. Try to delete that SSH key. It will ask to confirm the deletion then doing nothing. Logs show it tries to remove [email protected]. The UI shows the key listed as john.doe at example.com.
3. Try to connect to server.com via SFTP with the SSH key. It will not find the SSH key and say it failed due to bad username/password.

Expected behaviour

The program can parse a username with an @ in it and not assume the first term after the @ is the host.

Environment

• OS: Debian 12
• Architecture: x86_64
• Rust version: n/a
• termscp version: 0.13.0
• Protocol used: SFTP