`Ctrl+C`-ing the installer leaves the terminal without cursor

It'd be nice to restore the cursor if the installer is interrupted with `Ctrl+C`. I have to manually print `\e[?25h` to get it back (and I already had to `Ctrl+C` a couple of times in the last couple of days).

Start by locating the installer entry point and its Ctrl+C interruption handling in the Rust code. Run the installer, interrupt it during the affected state, and verify that the terminal cursor is restored afterward without manually printing the escape sequence.

Written by the indexing model from the issue text.