The two monolithic XSD content/identity rules only satisfied the OpenAPIKit
validation idiom at the wrong granularity: no per-constraint removability,
no isolable failing/near-miss tests. Split them into 32 named rules, each
finding tagged at its origin and cached per XSDContext so the walk still
runs once per document (the #101 decision against duplicating XSD's
recursive type resolution still holds). Wired the streaming path's ID/IDREF
and identity checks through the same framework instead of calling the
validators imperatively, and added the unwrapAndLookup combinator the rule
already named as required.
Also includes the mandated repo-wide swiftformat/swiftlint pass.
Add parseDocument, which builds a full HTML document by the HTML5
tree-construction insertion modes (initial, before html, before head, in head,
after head, in body):
- the result always has an html root containing a head and a body, whether or
not the source spelled those elements out.
- head-only elements (title, meta, link, base, style, script, and the rest)
are routed into the head; flow content starts and fills the body.
- explicit html, head, and body tags and their attributes are honored.
The existing fragment parser (parse) is unchanged, so tag-soup fragments still
round-trip without an implied wrapper.
Closes#69
