backend/script/test runs go test -timeout 30s -race -cover and, if
that fails, runs it again with -v and fails. The root script/test drops
its one 30-second timeout around both halves: from a cold Go build
cache, compiling the tests with -race used it all up. Each half keeps
its own limit. The race detector needs a C compiler: the Dockerfile
builder stage gains gcc and musl-dev, and script/bootstrap installs gcc,
with the C library headers on apt and apk, when gcc is missing; make
build still sets CGO_ENABLED=0. New tests: the health check's answer, a
valid report's answer, a report file's exact lines, and the flush at the
10 MiB threshold. The handlers TestImport stub is gone.
Model: opus-5-5
