fix some conformance issues

- include "html5-invalid" tests: these have some invalid markup but should still be able to be processed.
- use SPARQL to simplify tests
- improve property-copying algorithm (better than spec?)

Author: Porges

Cargo.lock

@@ -54,6 +54,10 @@ pretty_assertions = "1.4.1"
 rstest = { version = "0.26.1", default-features = false, features = [
     "crate-name",
 ] }
+serde = { version = "1.0.228", features = ["derive"] }
+serde_json = "1.0.149"
+spareval = "0.2.6"
+spargebra = "0.4.6"
 
 [target.'cfg(not(target_os = "windows"))'.dev-dependencies]
 librdfa-wrapper = { workspace = true }