build: install generated version header (#710)

Install the generated iceberg/version.h with the rest of the public
headers so installed packages expose the version macros.

Co-authored-by: Codex <codex@openai.com>

Author: manuzhang

src/iceberg/CMakeLists.txt

@@ -224,6 +224,8 @@ add_iceberg_lib(iceberg_data
                 ${ICEBERG_DATA_SHARED_INSTALL_INTERFACE_LIBS})
 
 iceberg_install_all_headers(iceberg)
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/version.h"
+        DESTINATION "${ICEBERG_INSTALL_INCLUDEDIR}/iceberg")
 
 add_subdirectory(catalog)
 add_subdirectory(data)