Checkpoint: The Generic Layer Cake

The task

Implement g_sort and g_dedup (see the challenge). The facade macro isort is given — your engine beneath it must be correct for ANY element type, and dedup must enforce its own precondition (sort internally). This is the module's thesis in two functions: the byte-level engine does the work, the type system lives in the callers.

Passing this proves you can write the layer C libraries actually ship: generic at the bottom, type-safe at the top, contracts in between.

Next module: the preprocessor — macros as a language over the language.