Palettes in JSON export missing shades

[tipa]

Describe the bug
The exported palettes only contain the shades 0, 5, 10, 15, 20, 24, 30, 35, 40, 50, 60, 70, 80, 90, 95, 98, 99 & 100.
However, several color roles reference other shades e.g. "Surface dim" is "neutral-87". Or "Surface Container Lowest" in the dark scheme is "netrual-4". These shades are missing in the JSON export.

Screenshots

Additional context
I want to programmatically generate my Android themes based on the JSON, mostly because exporting the Android XML is bugged. See these issues for context: #308, #313