Haha, awesome :D!
Yeah, I forgot to add a way to contact me, it's MinorLegato#1011 on discord : ).
The chunks were more of a design choice to separate the biomes/background images. In the beginning, I also thought about deactivating stuff outside of the current chunks, but as you said it was not necessary for any performance reasons. there is around 800-900 active entities in the beginning and my 6-year-old dying laptop was running it alright, I might change that system in the future though. But I do cull everything outside the view of the camera before rendering.
For the minimap, I marked the tiles that have been in the line of sight of the player with a flag, and then only rendered those tiles in the minimap. but you could keep track of that in a completely different structure if you wanted to. the line of sight algorithm I used is just a line trace between the player and close-by tiles and detecting if I intersect anything.
Feel free to tell me to elaborate on anything, on here or discord! :D