- rootUnion: union members get the same flattenability test as allOf members,
so a branch whose nested `allOf: [false]` makes it unsatisfiable is no
longer offered as a callable alternative with that constraint erased.
- selectBranchIndex: weigh only the pinned constants the caller SUPPLIED. One
it did not supply is a value this identification exists to seed, so
requiring it meant a deep link naming `kind` alone matched no branch
whenever the branches also pinned, say, a `version`. A supplied constant
that disagrees is still evidence against.
- admitsNull: `const: null` is conjunctive with its siblings, not an
override — `{ type: "string", const: null }` and
`{ const: null, anyOf: [...] }` reject every value, so the claim is made
only where the type and a sibling union leave null on the table.
Signed-off-by: cliffhall <cliff@futurescale.com>
f556f8831b