bench_scale sweeps the input size over four paths and reports time per
unit, so growth is visible even when absolute times move with the machine.
It shows SGP4 propagation and access search are flat per satellite, while
topology construction is quadratic and planning is quadratic in the number
of tasks.
The README said library code never uses expect, but twelve call sites do,
each guarded by a check on the line above or by construction. Allow that
case explicitly and record each site with its guard in the design notes.
README stated that a crate may only depend on layers to its left, but
nothing checked it, and the wording was self contradicting: the example
given for a cross layer jump was a reverse dependency. Clarify the rule,
add scripts/check-layers.sh to enforce it, run it in CI, and record the
boundary cases in docs/design/layers.md.
The cross-layer integration checks were examples containing assertions
that cargo test never ran, so a break in one layer's assumptions about
another could pass CI. Run them explicitly.
The benches/ and tests/ directories were empty placeholders that a virtual
workspace does not compile, and benches/criterion named a third party crate
this workspace forbids. Remove both and add a real zero dependency
benchmark as a facade example.