I wish I had figured this out earlier. I am incorporating code snippets, answers and a small cheat sheet in the root directory of my project in a markdown file. I have been googling things more than once and it is very frustrating.
Because it is a markdown file and I have what I googled as the heading with the answer link embedded. I have the code snippets in a
code block. I have important notes or the mistakes I keep making as bold. You can even incorporate images but fair warning at that point you should create a separate directory for the images. Here is a nifty vscode plugin
On a side note, you should also maintain an architecture.md. I may not be doing it in the right way but a very barebones nested list that describes the architecture of your project is far more convenient than checking the Trello board IMO.
Here is what my notes look like
This is nuxt/content btw