Harden translated routine coverage and ASAN fixes

[jamestjsp]

Summary

• add translation coverage/smell tooling and regression coverage for high-risk translated routines
• fix translated routine issues found in AB13HD, MB04HD, and SB10 logical workspace handling
• consolidate agent instructions into AGENTS.md and make CLAUDE.md refer to it

Verification

• scripts/check_translation_coverage.py --report-only
• scripts/check_translation_smells.py
• python3 -m py_compile scripts/check_translation_smells.py
• targeted pytest coverage added across affected routines
• ASAN Docker: ./scripts/run_asan_docker.sh --no-build tests/python/ -o addopts='' built and ran under ASAN with no AddressSanitizer memory report, but pytest failed one behavioral assertion: tests/python/test_mb03ld.py::TestMB03LDBasic::test_compq_c_orth_p expected neig == 3 and observed 4

Notes

• First ASAN Docker attempt failed before tests because the image lacks pytest-xdist while pyproject addopts injects -n auto; reran serially with pytest addopts cleared.
• Local worktree still has an unrelated unstaged .gitignore change for .ergo/lock, not included in this PR.