58th procedural mesh: 5-box double archway — 3 vertical posts
(left / shared center / right) plus 2 horizontal lintels each
spanning one opening. Pairs with the existing single
--gen-mesh-archway for plaza approaches, double-door tomb
fronts, formal garden entrances, paired temple entries.
Defaults to 1.40m × 2 openings with 2.40m opening height
(~3.16m total width × 2.60m height including lintels).
Splits the 138-line static-local kArgRequired array (the list
of flags requiring positional args) into a new
cli_arg_required.{hpp,cpp} module with extern linkage. Then
moves the three meta handlers that depended on it out of
main.cpp into cli_introspect.cpp:
- --validate-cli-help (uses the array for self-check)
- --version / -v (3-line printf)
- --help / -h (1-line passthrough)
main.cpp shrinks by 191 lines (677 to 486). Both the early
missing-argument detector in main() and --validate-cli-help
in cli_introspect.cpp now share one source of truth for the
arg-required list.