Sadly, I only just got a Pixel 8 myself and am still very new to it. The flowchart largely isn't needed for how linear this visual novel is once you choose a route, only serving to clarify optional content with different text, not a new route offshoot.
I am surprised the SVG doesn't zoom properly. I tried to export the flowchart to URL but it's too long to share here. And the image export is just too big for draw.io to do now.
Glad you've enjoyed the visual novel!