refactor: split 6 oversized packages into semantic subpackages
Structure debt list is now empty (FOLDER_DEBT = Set.of()), every folder
holds at most 4 java files:
- elytra/{mode,generator} -> elytra/core plus per-mode slices (close,
minspeed, obstacle, speeddemon, timetrial), 2 files each
- command/schematic -> command/schematic (4) + wand/ (2)
- generator/jump: JumpType -> jump/model/, SchematicBlockPlacer ->
jump/placement/schematic/
- player/core -> player/core (4) + PlayerSpawnSetup -> player/service (4)
18 files moved, imports/tests updated, 5 classes widened to public for
cross-package calls. No behavior change; check and build stay green.
loki5512344
4263df50a2
