go: no such tool 'covdata' fires when go test tries to build a test
binary for a package with zero _test.go files under -coverpkg. The
store package has no tests of its own (exercised via the server
harness); excluding it from the test command sidesteps the error
while -coverpkg still counts its coverage from server-side exercise.
Refs: M4.2
The store package has no test files of its own (its API is exercised
end-to-end through the server's eachStore harness against both Memory
and Postgres). Without -coverpkg, store/* shows 0% and drags the
total below the 70% gate even though every store method is run.
-coverpkg=./internal/... routes the instrumentation from server tests
into store + config + server alike.
Refs: M4.2
Minimal Go service: /healthz + /v1/tenants/by-slug/:slug + /v1/tenants/:id with an in-memory store seeded with the acme tenant. Stdlib-only; pgx + JWT validation land in M4.1 follow-up.
sharang