Update modonomicon demo content

[klikli-dev]

• [x] clean up demo book
  • [x] proper provider structure
  • [x] move lang content
• [x] clean up & improve datagen helpers/providers along the way
• [x] consider removing the separate demo mod and just refer to the demo book provider in the modonomicon code base (it is always up to date) for the desired version

[klikli-dev]

Closed in:

• 3f63f945d3eaa0d4b928d8cd62ebff0284b57ff5
• 2a661e7369cdb3278b8b945c06e9cf38653ef753
• e5ce81159ac554ce73952b2224ed78878c020734
• 5ccffc593ce5120501bd5afc37756dc9a6a27baa