feat(lance-graph-ontology): PR-bO-15 SchematronHydrator + ZUGFeRD rules

Second Tier-C hydrator. Schematron (ISO/IEC 19757-3) is the rule-
language layer that sits on top of XSD across every major e-business
standard — EN 16931, PEPPOL, XRechnung, ZUGFeRD, UBL, ISO 20022 all
ship structural XSD + behavioral .sch business rules. This hydrator
generalizes the rule-extraction shape so each future spec only needs
glue, not new hydrator code.

New SchematronHydrator (minimal name-extraction shape):
- crates/lance-graph-ontology/src/hydrators/schematron.rs
- Walks `<assert id="..." test="..." flag="...">` and
  `<report id="...">` and `<pattern id="...">` elements via quick-xml
  streaming, interns each as `{base_iri}/{element}/{id}`
- Additionally scans text bodies for bracketed business-rule IDs
  like [BR-52], [BR-CO-03], [BR-DE-1], [PEPPOL-EN16931-R008] —
  these are the canonical EN16931 / PEPPOL / DE / VAT-category rule
  identifiers used by cross-spec alignment. Each distinct ID interns
  as `{base_iri}/rule/{rule-id}`.
- Strict business-rule ID validator (uppercase-only, dash-segmented,
  no leading digit / double dash / trailing dash) keeps the rule
  namespace clean of false positives from message text.
- 3 unit tests verify the validator + end-to-end interning on a tiny
  in-memory .sch fixture.

bO-15 ZUGFeRD rules (OGIT::ZUGFERDRULES_V1, slot 31):
- hydrate_zugferd_rules() points the SchematronHydrator at the
  FACTUR-X_EN16931.sch file that already shipped with bO-16.
- Base IRI urn:schematron:factur-x-1.08-en16931 — stable URN for
  downstream alignment to PEPPOL / EN16931 / FeRD rule registries.
- inherits_from: Some(OGIT::ZUGFERD_V1.0) — rule namespace is
  meaningless without the structural CII namespace.
- 5 smoke tests verify the EN16931 anchor rules (BR-52 / BR-45 /
  BR-CO-03 / BR-CO-17 / BR-S-08 / BR-Z-08 / BR-DEC-19), PEPPOL
  extension (PEPPOL-EN16931-R008), schema-level FX-SCH-A-* IDs that
  KoSIT validator output references directly, and rule-family
  coverage (BR-CO / BR-DEC / BR-S / BR-Z / PEPPOL).
- ~510 IRIs hydrated: 301 distinct schema assert IDs (428 elements
  collapse to 301 — some IDs are reused across patterns) + ~209
  distinct bracketed business-rule IDs.

Inspection findings documented in tests + LICENSES/ZUGFERD.txt:
- 191 <report> elements present but NONE have @id (Schematron-1
  style; text bodies still contribute business-rule IRIs).
- 0 patterns / 0 phases with @id.

Side fix: factored out the XsdHydrator interning-closure type alias
to clear a clippy type_complexity warning. Now 5 clippy warnings,
all pre-existing oxrdf deprecations.

All 106 lance-graph-ontology tests pass; downstream consumers build
clean.

Author: claude

LICENSES/ZUGFERD.txt

@@ -42,10 +42,12 @@ up the Factur-X 1.08 EN16931 profile:
     standard_UnqualifiedDataType_100.xsd                (UDT)
 
 Plus the Schematron business-rule file `FACTUR-X_EN16931.sch` and
-the code-list database `FACTUR-X_EN16931_codedb.xml`. Neither is
-hydrated by the current XsdHydrator — they are shipped for future
-SchematronHydrator (business-rule projection) and CodeListHydrator
-(currency/unit code interning) PRs.
+the code-list database `FACTUR-X_EN16931_codedb.xml`.
+
+The `.sch` file is hydrated by SchematronHydrator (PR-bO-15) into
+the sibling slot OGIT::ZUGFERDRULES_V1 — see below. The codedb XML
+is shipped for a future CodeListHydrator PR (currency / unit / tax
+code interning), not hydrated today.
 
 Hydration
 ---------
@@ -67,3 +69,34 @@ Declares inherits_from: Some(OGIT::DOLCE_V1.0). Future alignment:
 These alignments are NOT baked into the XSDs (they're XML schema
 constraints, not OWL axioms); they're left to downstream consumers
 that need the cross-G projection.
+
+ZUGFeRD business rules (PR-bO-15)
+---------------------------------
+Hydrated as OGIT::ZUGFERDRULES_V1 via SchematronHydrator. Source:
+data/ontologies/zugferd/FACTUR-X_EN16931.sch (Apache-2.0, shipped
+in this repo alongside the XSDs).
+
+The hydrator interns every Schematron `<assert id="...">` ID and
+every bracketed business-rule identifier `[BR-NN]` / `[BR-CO-NN]` /
+`[BR-DEC-NN]` / `[BR-{S,Z,E,AE,G,IC,K,L,M,O}-NN]` / `[PEPPOL-EN16931-*]`
+found in message bodies. All IRIs live under the URN base
+`urn:schematron:factur-x-1.08-en16931/{assert,report,pattern,rule}/{id}`.
+
+Inspection of the EN16931 profile finds:
+
+  - 301 distinct `<assert>` @id values (some IDs are reused across
+    patterns, so 428 assert elements collapse to 301 IRIs).
+  - 191 `<report>` elements, none with @id (Schematron-1 style;
+    their message bodies still contribute business-rule IRIs).
+  - 0 patterns and 0 phases with @id.
+  - ~209 distinct bracketed business-rule IDs spread across the
+    EN16931 / PEPPOL / DE / VAT-category extension families.
+
+Total: ~510 IRIs in OGIT::ZUGFERDRULES_V1.
+
+Deferred follow-up:
+- XPath `<rule context="..."/>` resolution into edges back to XSD
+  types (would link `urn:schematron:.../rule/BR-52` ⊑ `ram:ApplicableTradeTax`).
+- Severity (`@flag="warning|error|fatal"`) projection.
+- Phase / pattern / rule structural edges.
+- `<let>` variable resolution.

crates/lance-graph-contract/build.rs

@@ -41,6 +41,11 @@ const CANONICAL_SLOTS: &[(&str, u32)] = &[
     // German hybrid PDF/A-3+XML invoice format aligned with EN 16931.
     // Hydrated as IRI-interning over UN/CEFACT CII XSDs via XsdHydrator.
     ("ZUGFERD", 30),
+    // L3 e-invoicing business rules (PR-bO-15). Schematron assertion /
+    // report IDs from the ZUGFeRD validator config, plus the bracketed
+    // EN16931 / PEPPOL / CO / DE business-rule IDs from the message
+    // bodies. Hydrated via SchematronHydrator.
+    ("ZUGFERDRULES", 31),
 ];
 
 fn canonical_slot(token: &str) -> Option<u32> {

crates/lance-graph-ontology/src/hydrators/mod.rs

@@ -25,6 +25,7 @@ pub mod owltime;
 pub mod provo;
 pub mod qudt;
 pub mod schemaorg;
+pub mod schematron;
 pub mod skos;
 pub mod xsd;
 pub mod zugferd;
@@ -36,6 +37,9 @@ pub use owltime::{hydrate_owltime, hydrate_owltime_from};
 pub use provo::{hydrate_provo, hydrate_provo_from};
 pub use qudt::{hydrate_qudt, hydrate_qudt_from};
 pub use schemaorg::{hydrate_schemaorg, hydrate_schemaorg_from};
+pub use schematron::SchematronHydrator;
 pub use skos::{hydrate_skos, hydrate_skos_from};
 pub use xsd::{collect_xsd_files, XsdHydrator};
-pub use zugferd::{hydrate_zugferd, hydrate_zugferd_from};
+pub use zugferd::{
+    hydrate_zugferd, hydrate_zugferd_from, hydrate_zugferd_rules, hydrate_zugferd_rules_from,
+};