Google Cloud observability adapters for the Culvert framework. Provides CloudTraceObservabilityHook (ObservabilityHook implementation backed by OpenTelemetry exporting spans to Cloud Trace via the GCP exporter) and DataCatalogLineageEmitter (LineageEmitter implementation that writes lineage events as Data Catalog tags on a configurable entry). Both registered via java.util.ServiceLoader. Sprint-2 deliverable (issue #24). Multi-contract module — ...