Forgotten Graves Continued

4.0.0: continuation of Forgotten Graves 3.2.26 (ginsm, MIT) for Minecraft 26.3 / Fabric Loader 0.20.1 / Java 25. Server-side only: the grave is a vanilla player head (decaying into skulls) and grave contents live in <world>/forgottengraves/graves.nbt instead of a custom block entity; protection by Level.setBlock/destroyBlock and ServerExplosion mixins; death hook at the start of Player.dropEquipment; documented properties config with /graves config reload; Trinkets, Inventorio, Cloth Config, Mod Menu, the client renderer and the status effect dropped; new /graves spawntest. Tested on a real 26.3 dedicated server (25 console checks).