[Task] Provide a Snap package.

My rationale is available at https://github.com/safing/portmaster-packaging/issues/45#issue-961633238:~:text=packages%20for%20snap%20are%20able%20to%20be%20distributed%20without%20necessitating%20containerization. Similar to https://github.com/kingToolbox/WindTerm/issues/799.

In case this has already been completed, please know that https://snapcraft.io/search?q=windterm provides no relevant results.

I am thankful for any assistance.

Start by reading the linked packaging rationale and comparing it with the current Snap search results for WindTerm. Determine the repository's packaging entry points and the requirements for a Snap package; the work is done when a relevant WindTerm Snap package is published and discoverable.

Written by the indexing model from the issue text.