feat(domain): add entities and json helpers for sqlite schema

backend/CMakeLists.txt

@@ -14,10 +14,13 @@ add_library(csp_core
   src/app_state.cc
   src/services/crypto.cc
   src/services/auth_service.cc
+  src/domain/enum_strings.cc
+  src/domain/json.cc
 )
 
 target_include_directories(csp_core PUBLIC
   ${CMAKE_CURRENT_SOURCE_DIR}/include
+  /usr/include/jsoncpp
 )
 
 target_link_libraries(csp_core PUBLIC
@@ -60,6 +63,7 @@ add_executable(csp_tests
   tests/sqlite_db_test.cc
   tests/auth_service_test.cc
   tests/auth_http_test.cc
+  tests/domain_test.cc
 )
 
 target_include_directories(csp_tests PRIVATE