STL codec: should use binary file format

I suggest to use the binary format for STL generation, or make it configurable

Start by tracing the CLI's output-conversion path for STL generation and determine how the current format is selected. The issue leaves open whether binary output should replace the existing format or be configurable, so clarify that choice before implementation. Done means STL generation produces the intended binary output or exposes the agreed configuration, with verification of both paths if applicable.

Written by the indexing model from the issue text.