Task: Build the par-rate DV01 and theta ladders

A party runs a par-rate DV01 ladder and a theta ladder, and each states the one figure it produces per trade and its unit.

• The par-rate ladder reads parsensitivity.csv, names the par instrument and tenor of each figure, and its configuration sets parSensitivity with a convention on every par instrument.
• The theta ladder reads the Theta risk factor rows of sensitivity.csv and states its ThetaPeriod.
• Neither ladder reports a figure in the zero-rate domain while claiming to be a par figure, and a test proves the two differ.
• The stored figures carry the shift family, so the reader can tell which size produced them.

(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.

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.

• Greek ladder reports — the design this task builds.