- Replace ecu_framework/config.py with ecu_framework/config/ package
(loader.py + __init__.py re-exports). Public surface unchanged — every
call site already uses 'from ecu_framework.config import ...' which
works identically for a module and a package. Brings config into the
same shape as lin/, power/, flashing/.
- Enrich loader.py with module-level design notes (pipeline diagram,
precedence rationale, "known wart" callout) and inline "why" comments:
the EcuTestConfig forward-reference quirk, the int(k, 0) hex-key trick,
_deep_update's mutate-in-place semantics, and the reason the in-memory
overrides are applied last despite being precedence #1.
- Add docs/23_config_loader_internals.md covering the merge semantics,
type-coercion philosophy, dataclass ordering quirks, PSU side-channel,
and the test-surface checklist (four places to touch when adding a
new config field).
- Fix the now-stale ecu_framework/config.py path in 01_run_sequence.md
and DEVELOPER_COMMIT_GUIDE.md.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
