ui.nu is a 5-line facade re-exporting UI primitives from clean.nu, error.nu,
help.nu, interface.nu, undefined.nu. All five used `export use X *` — ADR-025
transitivity rule prohibits these root star-re-exports.
Replaced each star with explicit symbol lists (19 symbols total):
clean.nu [cleanup] (1)
error.nu [throw-error safe-execute] (2)
help.nu [parse_help_command] (1)
interface.nu [13 symbols, one per line] (13)
undefined.nu [option_undefined invalid_task] (2)
The facade keeps the 2 callers (cmd/environment.nu, cmd/lib.nu) working with
their existing `use ../utils/ui.nu *` pattern — the consumers see identical
behaviour, but the symbol set is now explicit and bounded.
Validation:
nu --ide-check 50 ui.nu -> 0 errors
nu --ide-check 50 cmd/environment.nu -> 0 errors (regression check)
nu --ide-check 50 cmd/lib.nu -> 0 errors (regression check)
Refs: ADR-025, .coder/benchmarks/phase2-transitivity.md Layer 2
