Semantic Optimization Pipeline

Make proven facts survive into optimization — including algebraic structure. Ori's compiler already proves rich semantic facts about types, ownership, purity, and structure through the trait system, AIMS lattice, ARC pipeline, and type checker. But too many of these facts are consumed internally and discarded before they can benefit LLVM's optimizer. This plan extends existing infrastructure so that facts the compiler already proves travel one phase farther in the pipeline, and adds algebraic law metadata so that user-defined types (matrix, vector, bignum) receive the same algebraic optimizations that built-in types get today.