chore: unify naming schemes & remove redundant code

clients/CMakeLists.txt

clients/cpu_temp/src/cpu_temp.c

clients/test/CMakeLists.txt

clients/test/src/test.c

common/CMakeLists.txt

common/include/communication.h

common/include/message.h

common/include/protocol.h

common/include/userspace_comm.h

common/src/communication.c

common/src/message.c

common/src/protocol.c

common/src/userspace_comm.c

daemon/CMakeLists.txt

daemon/include/receive.h

daemon/include/send.h

daemon/src/main.c

daemon/src/receive.c

daemon/src/send.c

kernel/Makefile