rlang-conditions

Use when developing R packages that need to handle errors, warnings, and conditions properly. Covers: (1) cli_abort/cli_warn/cli_inform for throwing conditions with formatting, (2) Error call context with caller_env() and caller_arg(), (3) Input validation helpers that report the right function, (4) Error chaining with try_fetch() and parent argument, (5) Testing error conditions with testthat snapshots.