RetroBat separates every system after the first with a blank line.
json.dumps dropped all 100 of them: 100 hunks of noise in a diff meant
to show corrections. The separator is written again where the original
has it, and an added system takes it too where the original separates
them all. An empty truth gives back the cached file byte for byte.
Run ruff check --fix: remove unused imports (F401), fix f-strings
without placeholders (F541), remove unused variables (F841), fix
duplicate dict key (F601).
Run isort --profile black: normalize import ordering across all files.
Run ruff format: apply consistent formatting (black-compatible) to
all 58 Python files.
3 intentional E402 remain (imports after require_yaml() must execute
after yaml is available).
Abdessamad Derraz