feat(makefile): add TODO comments after mandatory adjustments

- Added "# todo" comments in the Makefile to indicate variables that need mandatory adjustments.

src/makefile/basic.mk

 # Configuration
 
 ## Server
-SERVER_USER := mmustermann
-SERVER_HOST := hyrican-1-extern
+SERVER_USER := mmustermann # todo
+SERVER_HOST := hyrican-1-extern # todo
 
 ## Python Environment
 SERVER_CONDA_PATH := /opt/conda
@@ -17,16 +17,16 @@ PYTHON_PACKAGES := tensorflow-cpu ipympl mypy jupyter pystan \
 
 ## Project Paths
 LOCAL_PROJECT_DIR := .
-REMOTE_PROJECT_DIR := ~/akis/my_project
+REMOTE_PROJECT_DIR := ~/akis/my_project # todo
 
 ## Project Files
-MAIN_SCRIPT := main.py
+MAIN_SCRIPT := main.py # todo
 LOG_FILE := progress.log
 
 ## File Transfer
-LOCAL_UPLOAD_FILES := .
-LOCAL_DOWNLOAD_DIR := download
-REMOTE_DOWNLOAD_FILES := output/*
+LOCAL_UPLOAD_FILES := . # todo
+LOCAL_DOWNLOAD_DIR := download # todo
+REMOTE_DOWNLOAD_FILES := output/* # todo
 
 ## Misc
 COPY_LINKS_AS_FILES := false