Implement level.dat reading and load the seed for use in world generation #1476

Job	Run time
Run lints (stable)	28s
Build project and test (ubuntu-latest, stable)	4m 23s
Run lints in release mode (stable)	28s
Build project in release (ubuntu-latest, stable)	1m 36s
Build project and test (windows-latest, stable)	10m 9s
Build project in release (windows-latest, stable)	4m 1s
Check formatting (stable)	13s
Build project and test (macos-latest, stable)	3m 35s
Build project in release (macos-latest, stable)	1m 36s
	26m 29s

Provide feedback