Module host 

The BashHost seam + Output. The host seam: BashHost is everything the pure evaluator needs from the outside world. Eval never touches a real filesystem or clock directly — it goes through this trait, so the lexer/parser/eval run unchanged under cargo test with an in-memory host and in the browser over OPFS.

v1 builtins are FS-ONLY (read/create/search) — no value-moving / lh-* platform commands (deferred to v2, see design/bashlite.md). A builtin receives its already-expanded args plus piped stdin, and returns an Output (stdout text + exit code). Builtins must be TOTAL: report errors as a nonzero exit + stderr text, never panic.

Structs

Output

The result of running one command: captured stdout/stderr text and an exit code (0 = success). Mirrors the { exit_code, stdout, stderr } shape the execute_script tool returns.

Traits

BashHost

The capabilities bashlite eval needs from its environment.