There is a function that invert the colors of your screen, you can pick either black on white or white on black, I have tried it and I have quite experience with your display, I think you should try this piece of code.
At the beginning of your Arduino code be sure that you declared the object using the same name.
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
To invert the display
To return the display again
As you said that you want a button to invert the display you might use this code I made
Or you might use Interrupts for better performance depending on your code.
As you couldn't find on the internet, I am student and I learn alot from the internet, to for example search for such a function in an Arduino library, try searching it's documentation or it's page on GitHub then afterwards see the function you want through the pages, but don't just search the function directly it will sometimes won't work as they are not that popular.
As a last thing Here is the documents where I got the function with it's parameters from.
I hope I've helped you out. any edits in the answer is well appreciated, as I am a student.