Answer prose round 1 and product-owner round 1: give goal 5.7 a test a reader can apply, drop the AGENTS.md copy of it, and cite the key decision to goal 5.5

todo.md

@@ -84,7 +84,7 @@
 | 81 | 0.2.0 | decision | **Refuse at load every `calc` operand not proven numeric and every divisor not proven nonzero, in a string column too.** | 4 | 4 | 6 | 8 | 6.1, 4 | 20.6 |
 | 36 | 0.2.0 |  | **Report every mistake a load finds in one error, as the decision "A load reports every mistake at once" states.** | 5 | 6 | 7 | 8 | 6 | 19.5 |
 | 88 | 0.2.0 |  | **Add a 12-digit `YYYYMMDDNNNC` form of `sv_SE.personnummer` and `sv_SE.samordningsnummer`, the form Skatteverket's testpersonnummer series and many systems store.** | 2 | 3 | 6 | 6 | 4 | 19.4 |
-| 41 | 0.2.0 |  | **Key every table by one key column, as the decision "A table selects by one key column, a code, never a free-form name" states.** | 6 | 7 | 7 | 8 | 5.7 | 19.1 |
+| 41 | 0.2.0 |  | **Key every table by one key column, as the decision "A table selects by one key column, a code, never a free-form name" states.** | 6 | 7 | 7 | 8 | 5.5 | 19.1 |
 | 52 | 0.2.0 |  | **Name the file a link error comes from beside its category path, `sub.x (/d/a/sub/x.json): …`.** | 1 | 2 | 5 | 7 | 6 | 19.0 |
 | 28 | 0.2.0 | decision | **Accept a middle name, and draw a `personnummer` whose sex matches a sex selected through a named pick.** | 4 | 4 | 6 | 7 | 4.1 | 18.9 |
 | 24 | 0.2.0 | defect | **Stop `misc.territory[EH].tld` rendering `.eh`, the one shipped TLD `misc.tld` does not hold.** | 1 | 1 | 4 | 7 | 4 | 18.6 |
@@ -231,7 +231,7 @@ Shape: T = table, t = template, c = choice.
 - Deletes the token-order rules (`drawsApart`, `readFold`, `branches`, the pairwise replay), the expansion hold fence, `drawGroup`, the own-family fence and the cell-reference fences, and revises the decisions that point here. The remaining draw checks are names, paths through names, cycles and the repeat cap.
 - Fixes on the way: `{/sel}|{/sel}` panics out of `Fake` today where two draws land on rows whose cells select different rows of another table; it must render.
 - Rewrites the README's Computation, References, Draw group, Correlated fields, Linked tables, Names and "One draw, one spelling" sections; the Linked tables section says which pick's weights govern a family, since the bound row decides.
-- Keeps a name read once where no reference can stand, such as `{/score as s}{calc(s * 2)}`, loading. Widens the refusal of a name read once to every binding, a path into it or a reference path bound included, since `{n.x}` read once is then `{/ref.x}`, and deletes the names fence over draw groups and nested repeats (`checkUses`, `readsHeld`).
+- Keeps a name read once where no reference can stand, such as `{/score as s}{calc(s * 2)}` over a numeric category `score`, loading. Widens the refusal of a name read once to every binding, a path into it or a reference path bound included, since `{n.x}` read once is then `{/ref.x}`, and deletes the names fence over draw groups and nested repeats (`checkUses`, `readsHeld`).
 - Say how a record's columns and a struct's tags read one pick, so the `first` and `sex` columns of one `sv_SE.person` record, or one struct's tags reading them, still describe one person.
 - Re-pin seeded output and `testdata/shipped_shape.txt` in their own commits; the CHANGELOG names the grammar change.