Install Prusti offline

[champignoom]

Steps to reprodce:

1. open some rust file in vscode
2. vscode shows "Installing Prusti"
3. and it never finishes

The problem is partly my network and proxy settings, which does not work very well the default installation script.

It would be nice if one can download and install prusti manually and then configure it in vscode offline.

I tried building prusti and putting path/to/prusti-dev/target/release in "Local Prusti Path" but it seems to be simply ignored without any diagnostics.

[fpoli]

When setting prusti-assistant.localPrustiPath, did you also set prusti-assistant.buildChannel to Local?

The prusti-assistant.localPrustiPath cannot just point to prusti-dev/target/release; it should point to some folder /path/to/foobar that has been populated with prusti-dev/x.py package release /path/to/foobar to properly include all the Z3 and Viper dependiencies.

[fpoli]

• We should make sure that it's possible to switch to the Local build channel even when the first activation happens offline or with a slow connection.
  • e.g. adding a timeout to the download step of https://github.com/viperproject/vs-verification-toolbox
• The readme should describe the localPrustiPath setting and its requirements.