fix: packaging bug and utilize dt from config

[PatrickNercessian]

The packaging bug was:

Installing the current project: forecasting-are (0.1.0)
Error: The current project could not be installed: No file/folder found for package forecasting-are
If you do not want to install the current project use --no-root.
If you want to use Poetry only for dependency management but not for packaging, you can disable package mode by setting package-mode = false in your pyproject.toml file.
If you did intend to install the current project, you may need to set packages in your pyproject.toml file.