chore: import upstream snapshot with attribution

rust/perspective-server/cpp/protos/CMakeLists.txt

@@ -0,0 +1,36 @@
+cmake_minimum_required(VERSION 3.18.2)
+project(perspective-protos)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+
+option(PSP_PROTO_PATH "Path to the perspective proto directory" "")
+
+if(NOT DEFINED psp_build_message)
+    function(psp_build_message message)
+        set(BUILD_MESSAGE "${BUILD_MESSAGE}\n${message}")
+    endfunction()
+endif()
+
+# Include the FindProtobuf.cmake module
+list(APPEND CMAKE_MODULE_PATH "../../cmake/modules")
+
+find_package(Protoc REQUIRED)
+find_package(InstallDependency REQUIRED)
+
+if(NOT DEFINED PSP_CMAKE_MODULE_PATH)
+    set(PSP_CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/../../cmake")
+    message(STATUS "PSP_CMAKE_MODULE_PATH not defined, using ${PSP_CMAKE_MODULE_PATH}")
+endif()
+
+psp_build_dep("protobuf" "${PSP_CMAKE_MODULE_PATH}/protobuf.txt.in")
+
+set(PROTO_FILES "${PSP_PROTO_PATH}/perspective.proto")
+
+protobuf_generate_cpp(PROTO_SRCS PROTO_HDRS ${PROTO_FILES})
+add_library(protos STATIC ${PROTO_SRCS} ${PROTO_HDRS})
+target_include_directories(protos PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/protobuf-src/src)
+target_include_directories(protos PUBLIC ${CMAKE_BINARY_DIR}/protos-build)
+target_link_libraries(protos protobuf::libprotobuf)