fix(stats): use compatible Bukkit registry keys

design/user-stories/us-004-capture-player-snapshots.md

@@ -12,6 +12,7 @@ As a **server analyst**, I want periodic player location and statistic snapshots
 ## Acceptance criteria
 
 - [x] Each configured interval captures every online player's world identity, coordinates, orientation, game mode, and biome.
+- [x] Registry-backed snapshot values use Bukkit's stable `Keyed` contract so collection remains compatible with the supported Purpur runtime.
 - [x] Every Bukkit untyped, block, item, and entity statistic combination accepted by Bukkit is captured, including zero values.
 - [x] Invalid statistic subtype combinations are skipped without stopping the snapshot.
 - [x] Statistic reads are spread across ticks according to a configurable operation budget and run through Bukkit scheduling.

src/main/java/games/dmg/spigotevents/stats/BukkitRegistryKeys.java

@@ -0,0 +1,17 @@
+package games.dmg.spigotevents.stats;
+
+import org.bukkit.Keyed;
+import org.bukkit.NamespacedKey;
+
+final class BukkitRegistryKeys {
+    private BukkitRegistryKeys() {}
+
+    static NamespacedKey get(Keyed value) {
+        return value.getKey();
+    }
+
+    static String format(Keyed value, String fallback) {
+        NamespacedKey key = get(value);
+        return key == null ? fallback : key.toString();
+    }
+}

src/main/java/games/dmg/spigotevents/stats/PlayerSnapshotCollector.java

@@ -44,8 +44,7 @@ public final class PlayerSnapshotCollector {
         data.put("pitch", location.getPitch());
         data.put("game_mode", player.getGameMode().name().toLowerCase());
         var biome = location.getBlock().getBiome();
-        var biomeKey = biome.getKeyOrNull();
+        data.put("biome", BukkitRegistryKeys.format(biome, biome.toString()));
-        data.put("biome", biomeKey == null ? biome.toString() : biomeKey.toString());
         publish("player.location", identity(player), data);
     }
 
@@ -157,9 +156,13 @@ public final class PlayerSnapshotCollector {
                 if ((blocksOnly && !material.isBlock()) || (!blocksOnly && !material.isItem())) {
                     continue;
                 }
+                var materialKey = BukkitRegistryKeys.get(material);
+                if (materialKey == null) {
+                    continue;
+                }
                 try {
                     target.put(
-                            statistic.getKey() + "/" + material.getKeyOrThrow(),
+                            statistic.getKey() + "/" + materialKey,
                             currentPlayer.getStatistic(statistic, material));
                 } catch (IllegalArgumentException ignored) {
                     // Bukkit rejects combinations not represented by the game.
@@ -180,9 +183,13 @@ public final class PlayerSnapshotCollector {
             while (operations < budget && subtypeIndex < ENTITY_TYPES.length) {
                 EntityType entityType = ENTITY_TYPES[subtypeIndex++];
                 operations++;
+                var entityTypeKey = BukkitRegistryKeys.get(entityType);
+                if (entityTypeKey == null) {
+                    continue;
+                }
                 try {
                     target.put(
-                            statistic.getKey() + "/" + entityType.getKeyOrThrow(),
+                            statistic.getKey() + "/" + entityTypeKey,
                             currentPlayer.getStatistic(statistic, entityType));
                 } catch (IllegalArgumentException ignored) {
                     // Bukkit rejects unsupported entity types.

src/test/java/games/dmg/spigotevents/stats/BukkitRegistryKeysTest.java

@@ -0,0 +1,24 @@
+package games.dmg.spigotevents.stats;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+import org.bukkit.NamespacedKey;
+import org.bukkit.Keyed;
+import org.junit.jupiter.api.Test;
+
+class BukkitRegistryKeysTest {
+    @Test
+    void formatsARegisteredKey() {
+        Keyed keyed = () -> NamespacedKey.minecraft("plains");
+
+        assertEquals("minecraft:plains", BukkitRegistryKeys.format(keyed, "fallback"));
+    }
+
+    @Test
+    void reportsAnUnavailableKey() {
+        Keyed keyed = () -> null;
+
+        assertNull(BukkitRegistryKeys.get(keyed));
+    }
+}