Refactor ui's hardcoded ANSI constants into a Theme over semantic roles (default = byte-identical output, golden tests unchanged), then add built-in retro themes cga/green/amber. Selection via hidden easter-egg flags (-cga/-green/-amber) and the documented STRUCTALIGN_THEME env var. Not a full theming system. Lands in two PRs: Theme abstraction, then palettes+selection.
Refactor
ui's hardcoded ANSI constants into aThemeover semantic roles (default = byte-identical output, golden tests unchanged), then add built-in retro themescga/green/amber. Selection via hidden easter-egg flags (-cga/-green/-amber) and the documentedSTRUCTALIGN_THEMEenv var. Not a full theming system. Lands in two PRs: Theme abstraction, then palettes+selection.