Task: Show a curve's documentation once

(Describe what user-visible-or-internal change this task produces.)

(Implementation strategy. Written when work starts; key decisions are distilled into the parent story's * Decisions at close, but the plan itself stays — it is the historical record of what we did.)

Every number this task claims about a tree, with the command that produced it and the commit it was measured at. A number without both is not a measurement, because a clean-up record describes a tree and trunk moves under a branch: a consumer count, a gate's component count and a suite's size all change with no code changing, and the reader of a bare number cannot tell which tree it came from. Where the raw output matters, put it in an evidence/ file beside the task and name that file in the Command column.

• One sentence, two places. The contract gives a curve leaf a help and a description that are the same guide line, so the row's hint and the documentation panel printed it twice. The hint is gone: a row that is read and not changed states its label and its value, and the documentation is read where it is collapsed, which is what the ORE element and leaf screen standard states for a leaf in read mode. The engine settings and conventions screens already draw it this way, so this page was the odd one out.

Manual QA scenarios (scaffolded via compass add test_scenario) that verify this task. Link new ones here as they're created; the scenario doc itself links back via its "Verifies task" field.

A curve's documentation appears once, in the panel it is collapsed under. The row states the label, the required mark and the value, as the engine settings and conventions screens do, and the ten browser tests include one that fails if the sentence returns under the value.