### A figure shown as what it is: the unmetered marker never reads as zero joules

- **`wai-rs`**: `energy_class::Presented` is the one rendering of a figure for a reader. The
  unmetered marker reads `unmetered`; a figure with no class says that nothing states how it
  was obtained; a figure whose coverage is `Partial` reads "at least" (energy-measurement §9.1);
  a classed figure carries its class and, where it has one, its declared uncertainty over its
  window, all in integer arithmetic (`joules_text`). A class beside a zero figure, a lower bound
  of nothing and a figure below the resolution floor are refused, as every verifier refuses
  them, so nothing is shown that a verifier would not accept.
- **`wai-web`**: `energyText` binds it for a page. The world demo sealed a session it never
  timed as the unmetered marker yet printed "≈0.0 mJ (Estimator …)" beside it; it now shows that
  session as `unmetered`, and a timed one as its `Estimator` figure with the declared power it
  rests on.