fix: Guard --headless flag with DEMO_HEADLESS define

Prevents user confusion when DEMO_HEADLESS is not defined at compile time.
The --headless and --duration flags are now only available when headless
support is compiled in.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/src/main.cc b/src/main.cc
index 58ea124..6132841 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -61,11 +61,13 @@ int main(int argc, char** argv) {
       }
     } else if (strcmp(argv[i], "--tempo") == 0) {
       tempo_test_enabled = true;
+#if defined(DEMO_HEADLESS)
     } else if (strcmp(argv[i], "--headless") == 0) {
       headless_mode = true;
     } else if (strcmp(argv[i], "--duration") == 0 && i + 1 < argc) {
       headless_duration = atof(argv[i + 1]);
       ++i;
+#endif
     } else if (strcmp(argv[i], "--hot-reload") == 0) {
       hot_reload_enabled = true;
       printf("Hot-reload enabled (watching config files)\n");
@@ -190,7 +192,7 @@ int main(int argc, char** argv) {
   }
 #endif
 
-#if !defined(STRIP_ALL)
+#if !defined(STRIP_ALL) && defined(DEMO_HEADLESS)
   // In headless mode, run simulation without rendering
   if (headless_mode) {
     printf("Running headless simulation (%.1fs)...\n", headless_duration);