r4subpharma 0.1.0

• Initial release.
• as_variable_metadata(): normalize a metacore object or a data.frame into the shared variable-metadata contract used by the adapters.
• metacore_to_evidence(): convert metadata into R4SUB documentation evidence, reusing the Q-DEFINE-002 and Q-DEFINE-003 indicators.
• adam_to_evidence(): check an ADaM dataset against its metadata and emit presence, unexpected-variable, type, and label evidence (T-ADAM-001, T-ADAM-002, Q-ADAM-001, Q-ADAM-002).
• submission_readiness(): harvest evidence from metadata and one or more ADaM datasets and compute the Submission Confidence Index in a single call.
• Added the cdisc-pilot vignette, a worked case study that scores the CDISC pilot ADaM package using public metacore and pharmaverseadam data.