autocodebook - Automatic Codebook and Tracking for 'Spark' and 'dplyr' Pipelines

Wraps 'dplyr' verbs (mutate, summarise, filter) to automatically capture variable metadata (type, source columns, categories, and source code), producing a codebook and eligibility tracking table with zero manual documentation. Works with both 'sparklyr' (tbl_spark) and local data frames. Adds big-data optimizations (caching, assume-unique counting, checkpointing) and a standardized report module with an eligibility flowchart, editable codebook export (HTML, DOCX, XLSX), and cross-sectional or longitudinal variable inspection.