static checks: PASS
ruff check (F399 Python files): PASS
ruff format check (F399 Python files): PASS
py_compile: PASS
git diff check (F399 files): PASS
diagram SVG/PNG parse, 2700x1620 dimensions, nonblank and visual inspection: PASS
randomized properties: 3 x 1000/1000 PASS
full Python exact-identity gate: 989 passed + 235 subtests, zero degradation
full LLVM 17 lit: 261 discovered, 259 passed, 2 unsupported, 0 failed
clang-format: not applicable (F399 has no C/C++ source change)
coverage/speedup/public-target claim: intentionally absent