ctx-exec — token-efficient command output compression.
Compresses captured command output while keeping the signal: lines that
match critical patterns (error, warning, failed, panic, …) or user-supplied
--keep patterns survive verbatim, the first/last few lines form a summary
head/tail, and everything in between folds into a single deterministic
marker: ... [N lines omitted].
Matching is rule-driven with the regex crate — the same engine ripgrep
uses — so patterns follow rg's default regex syntax (case-insensitive by
default, matching rg's default behavior).
Byte-stable by design: output is a pure function of the input text and the options. No timestamps, no counters, no environment dependence.