enable otel exporter

CMakeLists.txt

@@ -54,7 +54,7 @@ if(ZT1_CENTRAL_CONTROLLER)
     set(CMAKE_CXX_STANDARD 17 CACHE STRING "C++ standard to conform to" FORCE)
     set(CMAKE_CXX_STANDARD_REQUIRED True CACHE BOOL "C++ standard required" FORCE)
     set(CMAKE_CXX_EXTENSIONS ON CACHE BOOL "Enable compiler-specific extensions" FORCE)
-    add_definitions(-DZT_NONFREE_CONTROLLER=1 -DZT_CONTROLLER_USE_LIBPQ=1 -DZT1_CENTRAL_CONTROLLER=1)
+    add_definitions(-DZT_NONFREE_CONTROLLER=1 -DZT_CONTROLLER_USE_LIBPQ=1 -DZT1_CENTRAL_CONTROLLER=1 -DZT_OPENTELEMETRY_ENABLED=1)
     set(CONTROLLER_RUST_FEATURES ztcontroller)
     set(RUST_BUILD_COMMAND cargo build --release -F ${CONTROLLER_RUST_FEATURES})
 else()