Audit Nx Tasks

[threeal]

This pull request makes the following modifications to the Nx configuration:

• Moves Nx inputs and task declarations from the package.json to the nx.json.
• Updates scripts in the package.json to no longer use the nx exec commands. Instead, it is now recommended to directly run the nx command (e.g., yarn nx run build) to utilize Nx effectively.
• Adjusts the inputs of each task to ensure caching is triggered only if the appropriate files are changed.

These changes retain the usage of Nx in this project while improving the organization and efficiency of our tasks. This pull request effectively closes #36.