[endec] clearer error message on EdmElement#asMap, return default val…

…ue in EdmMap#getWithErrors if key is not present

src/main/java/io/wispforest/owo/serialization/format/edm/EdmElement.java

@@ -42,7 +42,7 @@ public Object unwrap() {
 
     public EdmMap asMap() {
         if(this.type != Type.MAP) {
-            throw new IllegalStateException("Given Element is not a Map Type: " + this);
+            throw new IllegalStateException("Cannot cast EDM element of type " + this.type + " to MAP");
         }
 
         return new EdmMap(this.cast());

src/main/java/io/wispforest/owo/serialization/format/edm/EdmMap.java

@@ -14,6 +14,7 @@ public final class EdmMap extends EdmElement<Map<String, EdmElement<?>>> impleme
 
     @Override
     public <T> T getWithErrors(@NotNull KeyedEndec<T> key) {
+        if (!this.has(key)) return key.defaultValue();
         return key.endec().decodeFully(EdmDeserializer::of, this.value().get(key.key()));
     }