A simple wrapper around the https://github.com/deadsy/sdfx Go-based solid modeling package. Re-enables fluent-style code when it's okay to panic.
Needed because we removed panics in core code in deadsy/sdfx#24, deadsy/sdfx#26, and deadsy/sdfx#27. Background and rationale discussed in more detail in deadsy/sdfx#50 and deadsy/sdfx#51.