When using GitLab (either the official or a self-hosted instance), it is recommended to set up a Secure Shell (SSH) key to allow a secure connection between GitLab and your local environment.
I couldn’t find a way to include code snippets from separate code files in markdown documents in the way that I wanted (specified in the frontmatter and with the ability to choose which lines to import), so I created my own Remark plugin (with some help from Claude 🤖). Now I can use the shortcode :code[1-4]: to get exactly the code I want!