- rootUnion reads every composition keyword through `membersOf` and every
`required` through `requiredOf`. These schemas describe the wire and each
member arrives as `unknown`, so `anyOf: {}` or `required: "x"` really
can arrive — and reading them as lists threw, taking all three clients down
rather than declining one malformed tool. Both web and TUI required-field
checks are guarded the same way.
- admitsNull evaluates a sibling `anyOf` beside a `const: null` instead of
refusing outright: the union decides in both directions, and
`{ const: null, anyOf: [{ type: "null" }] }` admits null as plainly as an
all-string union rejects it. Refusing it left a read-only required field
seeded with the only value it accepts and submit permanently disabled.
Signed-off-by: cliffhall <cliff@futurescale.com>