fix: resolve build warnings

pom.xml

@@ -68,6 +68,18 @@
                 <artifactId>maven-shade-plugin</artifactId>
                 <version>3.6.0</version>
                 <configuration>
+                    <transformers>
+                        <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer"/>
+                    </transformers>
+            <filters>
+                        <!-- Keep the plugin manifest; dependency manifests describe separate JARs. -->
+                        <filter>
+                            <artifact>org.bstats:*</artifact>
+                            <excludes>
+                                <exclude>META-INF/MANIFEST.MF</exclude>
+                            </excludes>
+                        </filter>
+                    </filters>
                     <createDependencyReducedPom>false</createDependencyReducedPom>
                     <relocations>
                         <relocation>

src/main/java/net/tfminecraft/musicalinstruments/items/ItemResolver.java

@@ -1,5 +1,7 @@
 package net.tfminecraft.musicalinstruments.items;
 
+import net.tfminecraft.musicalinstruments.util.LegacyModelData;
+
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
@@ -84,6 +86,8 @@ private ItemStack resolveVanilla(String path) {
     }
 
     // modeled(type=paper;name=&6Flute;model=1001)
+    // Keep the existing legacy text representation, formatting, and exact-string comparisons.
+    @SuppressWarnings("deprecation")
     private ItemStack resolveModeled(String path) {
         int open = path.indexOf('(');
         int close = path.lastIndexOf(')');
@@ -114,7 +118,7 @@ private ItemStack resolveModeled(String path) {
             }
             if (attributes.containsKey("model")) {
                 try {
-                    meta.setCustomModelData(Integer.parseInt(attributes.get("model")));
+                    LegacyModelData.set(meta, Integer.parseInt(attributes.get("model")));
                 } catch (NumberFormatException e) {
                     logger.warning("Invalid model data in modeled item '" + path + "'.");
                 }

src/main/java/net/tfminecraft/musicalinstruments/util/LegacyModelData.java

@@ -0,0 +1,36 @@
+package net.tfminecraft.musicalinstruments.util;
+
+import java.util.List;
+import org.bukkit.inventory.meta.ItemMeta;
+import org.bukkit.inventory.meta.components.CustomModelDataComponent;
+
+/** Preserves the integer model IDs used by existing configuration and resource packs. */
+public final class LegacyModelData {
+    private LegacyModelData() {}
+
+    public static boolean has(ItemMeta meta) {
+        return !meta.getCustomModelDataComponent().getFloats().isEmpty();
+    }
+
+    public static int get(ItemMeta meta) {
+        List<Float> floats = meta.getCustomModelDataComponent().getFloats();
+        if (floats.isEmpty()) {
+            throw new IllegalStateException("We don't have CustomModelData! Check hasCustomModelData first!");
+        }
+        return floats.get(0).intValue();
+    }
+
+    public static void set(ItemMeta meta, Integer value) {
+        if (value == null) {
+            meta.setCustomModelDataComponent(null);
+            return;
+        }
+        CustomModelDataComponent component = meta.getCustomModelDataComponent();
+        // The former integer setter replaced the entire component, not just its first float.
+        component.setFloats(List.of(value.floatValue()));
+        component.setFlags(List.of());
+        component.setStrings(List.of());
+        component.setColors(List.of());
+        meta.setCustomModelDataComponent(component);
+    }
+}