Group @testable imports at the bottom, per public/rules-swift's swiftformat. A
behavior-preserving import-ordering reformat across 252 files (mostly tests).
--trailingclosures was deliberately not adopted (cosmetic, and swiftformat flags
it as caution-worthy).
A default/fixed value on an element or attribute whose type names a user-declared
type in the schema's own target namespace must be a valid value of that type
(XSD 1.0 e-props-correct.2 / a-props-correct.2). The check runs after the named
types are compiled and validates with the compiled SimpleType validator (the one
instance validation uses), so whitespace and facet handling match. Built-ins are
handled at structure time; imported, foreign, and inline anonymous types are left
alone via a namespace gate.
This exposed a pre-existing compile defect: a simpleType restriction read its base
only from the base attribute, so an inline anonymous <simpleType> base (a list or
union with no base attribute) was dropped and the type collapsed to an atomic
string, making a length facet count characters instead of list items. The
restriction branch now resolves the inline child as its base, preserving list and
union variety. This corrects both schema-time value checking and instance
validation.
XSTS: invalid schemas accepted 462 to 454; invalid instances accepted 160 to 158;
no other bucket raised.
