One command now measures the branch against its merge-base: builds both
revisions, runs a fixture A/B (isolated per-binary stores, alternating
rounds), optional strictly-read-only probes of real apps, and the
synthetic locator benchmark, then renders a self-contained report.html
with validated light/dark palettes, grouped p50/p95 bars, honesty
callouts for non-comparable defaults, and table fallbacks. Replaces the
markdown summary and the standalone locator-report generator, whose
sanitized-report flow required manual invocation and hardcoded sizes.
