Ported from make/utils.mk, make/def.mk, make/apps/def.docker.mk and
make/apps/def.mk, with the examples that sat as dead comments in
make/apps/def.mk turned into actual assertions.
Two deviations from the make macros are pinned and documented in DELTAS.md;
both only show up on code paths nothing uses.
- spec/golden/cases.txt: 69 black-box cases (CLI wrapper mode and make
include mode) run in a hermetic sandbox with a mocked docker
- spec/golden/expected/*.txt recorded from this engine (baseline)
- make test / test-golden / golden-record / lint dev targets
Yann Autissier