* Module: improve doc comments
* C backend: improve const-correctness
* C backend: introduce renderTypeAndName
* C backend: put `static` on functions when appropriate
* C backend: fix not handling errors in genBinOp
* C backend: handle more IR instructions
- alloc, store, boolean comparisons, ret_ptr
* C backend: call instruction properly stores its result
* test harness: ensure execution tests have empty stderr