feat: add fzf-based file/plugin/port selection and update build system

client/tests/test_tui_stub.c

@@ -0,0 +1,5 @@
+#include "tui.h"
+
+char *tui_fzf_select(const char *const items[], size_t count, const char *prompt){(void)items;(void)count;(void)prompt;return NULL;}
+
+void tui_cleanup(void){}