Docs: Update Example Generation Setup

[kalib-brayer]

Added bash files to make example loading and updating easier. Now the user can call on a bash file to load or update data instead of manually updating a bash script each time. I also updated the data loading scripts to reference the new bash files.

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[kalib-brayer]

@LukaFontanilla I added a single shared environment file so the developer only needs to fill in the values one time. I also added explicit directions on updating the .env file to reference the necessary variables before running the scripts to load the examples. I simplified the bash scripts to reference the single .env file too.