App Properties File

Create a app.properties file in the root of the repo according to [Setup and Configuration Guide specifications](https://docs.google.com/presentation/d/1hvnwv76gX98nAAgTxJp47CremzwPkfzDkXgejQGz2l0/edit#slide=id.g7840023276_31_0)

Start with the Setup and Configuration Guide linked in the issue, then inspect the repository root to confirm where app.properties belongs. Create the root-level file according to the guide's specifications; done means the file exists there and matches the documented configuration.

Written by the indexing model from the issue text.