Every frontend repeated the same target wiring (glob sources minus main.cpp →
essim_<name> lib linking essim_core; essim exe from main.cpp linking the lib +
essim_frontend; RUNTIME_OUTPUT_DIRECTORY=build/). Move it into a reusable
helper cmake/EssimFrontend.cmake::essim_add_frontend(name LIBS ...), included
once at the top level.
The tui CMakeLists now just fetches FTXUI and calls
essim_add_frontend(tui LIBS ftxui::screen ftxui::dom ftxui::component). A new
frontend's CMakeLists is its toolkit setup + one call. No behaviour change;
binary stays ./build/essim, tests green.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
François
e561c0f960