STYLE-005: ElementStyleSectionHost wraps ElementStyleSection with
SuggestionBanner. Uses useStyleSuggestions + executeSuggestionAction.
propertyeditor.ts updated to use host (drop-in, zero API change).
UBA-001: types.ts — Field discriminated union (8 types), BackendMetadata,
Section, Condition, ParseResult<T>. Zero external deps.
UBA-002: SchemaParser.ts validates pre-parsed objects against UBA v1.
Forward-compat: unknown field types/versions produce warnings not errors.
22 unit tests in tests/models/UBASchemaParser.test.ts.
