Skyveil Cloudlands Pass 2 Notes

Focus:
- Better high-sky movement feel after the first cloud island prototype.
- Added drift-fall safety when falling near Skyveil cloud blocks in the high cloud layer.
- Added test/debug commands to make manual visual testing easier without waiting for automatic generation.

New commands:
/skyveilcloudlands generate_trail <count>
  Generates a loose trail of cloud islands in the command source/player look direction.

/skyveilcloudlands scan_near <radius>
  Counts Skyveil cloud blocks near the command source and reports the nearest cloud block position.

New config keys:
enable_cloudlands_drift_fall = true
cloudlands_drift_fall_min_y = 220
cloudlands_drift_fall_scan_down = 28
cloudlands_drift_fall_horizontal_radius = 3
cloudlands_drift_fall_ticks = 60
cloudlands_debug_scan_max_radius = 64

Notes:
- This pass does not add mobs, villages, portals, bosses, or a separate dimension.
- Cloud worldgen remains the existing server-safe prototype around loaded players and manual commands.
- Build validation must be run on the user's Windows Minecraft project because this sandbox cannot rely on the NeoForge Gradle environment.
