Merges one page's stopJSCoverage() result into config.state.results.coverage. No-op unless
coverage is enabled and a source-map decoder is present. Only the test bundle is attributed;
node_modules sources are dropped here (test entry files are dropped later, in the report layer).
Builds a self-contained HTML report: a summary table plus per-file source with line coloring.
Builds a standard LCOV lcov.info string (line coverage only: DA/LF/LH per file).
Turns the raw coverage map into sorted, test-file-filtered rows with computed percentages.
Renders the run's accumulated coverage: always prints the terminal summary, then writes the
lcov/html reports the user requested via config.coverageFormats. testFiles (the run's
test entry paths) are excluded so the report reflects the code under test, not the tests.
Coverage report rendering — writes the report and builds its rows/lcov/html forms.
Usage
import * as mod from "lib/coverage/index.ts";