KineticForces — single registry for method flags, docs, and names #248

KineticForcesControl (KineticForcesStructs.jl:17-34), KineticForcesInternal.methods / .docs (KineticForcesStructs.jl:184-206), and Compute.jl:161-168 flags all enumerate the same 18 NTV methods in the same order. Three parallel structures that must stay in sync. Refactor to a single const METHOD_REGISTRY = (...) and derive the rest. Low priority but drift-prone. PR #112 adds a guard test that asserts equal lengths; this issue replaces the guard with a real registry.