Flow diagnostics (TOF + tracer partition + Lorenz)
Research-grade — validation in progress.
**v9 Gap C** ships forward/backward time-of-flight, injector/producer tracer partition, allocation matrix, Lorenz coefficient + sweep-efficiency estimate via `src/lib/reservoir/flowDiagnostics.ts` — cheap pre-simulation drainage picture matching MRST `diagnostics` + JutulDarcy. Live UI surfaces: `FlowDiagnosticsCard` mounted at the bottom of `/economics` (5-spot allocation matrix demo) and `TofIsochroneCard` opt-in on `/parent-child` under the plan view (per-parent drainage share % + median residence time + Lorenz heterogeneity rank from an inverse-distance² stage→parent flux proxy). 9 drift-guards lock conservation, single-injector mass split, and Lorenz monotonicity.
Promote the inverse-distance² stage→parent flux proxy on `/parent-child` to a true post-IMPES Darcy face-flux source so allocation shares come from the live `compositionalBlackOil3P` solve (today's proxy is qualitative). Add a forward-TOF isochrone overlay to the plan-view SVG so engineers can visually rank stages by drainage cycle-time, not just by per-parent share.
No phase markers extracted from this row's prose yet.
- No published error band yet — use with engineering judgment.