Copilot round 10: one finding, the last position of the rule the previous two
rounds established. A *non-null* branch can carry its own `anyOf`, and the
hoist drops it — the branch's `anyOf` overwrites the wrapper's in the spread
and is then cleared, so `{ anyOf: [{ type: "string", anyOf: [{ const: "a" }] },
{ type: "null" }] }` widened into an unconstrained nullable string.
Rather than add a fourth inline condition, the four sites that ask "does this
schema compose something I cannot evaluate?" now share one predicate,
`hasUnevaluatedComposition` (an opaque applicator, or a nested `anyOf`):
- the surviving branch in the `anyOf` collapse (this round's finding),
- the null branch in `admitsNull`,
- the `type: [T, "null"]` collapse path,
- and, via `hasOpaqueApplicator`, the top of `admitsNull`.
Each of those was missed independently across rounds 8-10 for the same reason:
the guard existed but was spelled out inline at each site and drifted. Sharing
the predicate is the part that stops a fifth site from repeating it.
Signed-off-by: cliffhall <cliff@futurescale.com>
562709a79a