inspector updates and dropdowns

the inspector now has IOR and transmission values that you can change, ui updates, and dropdowns
 
this took literally like 45 epochs because i was running into a materialgpu indexing issue where the inspector boxes would update the wrong values and my peanut brain didnt even think to check if i set the indices correctly
 
dropdowns also took a good 3-4 hours, but it wasnt too bad, mostly just figuring out the correct logic
 
in total, the dropdown class (ui_dropdown.cpp/hpp) is at 169 lines, and the inspector class (ui_inspector_panel.cpp/hpp) is at 470 lines

next, i think ill either work on ui rounding or a file hierarchy viewer