Create more syntax frontends for AutoCorrode

AutoCorrode at heart is a generic framework for reasoning about imperative programs with separation logic. Currently, the framework is instantiated with a Rust-like frontend called μRust but there is nothing particularly Rust-specific about the framework, and new frontends could be added for reasoning in different imperative languages, like C.

The issue names only the existing μRust frontend; start there to understand how AutoCorrode instantiates its generic framework. Choose a target language such as C and determine the files, entry points, and acceptance checks needed for a new frontend. Done means an additional syntax frontend is integrated with the framework.

Written by the indexing model from the issue text.