fix: 🐛 if resource doesn't have 'json' schema, embed it instead of referencing it

There may be resources that don't have the 'json' schema but only the 'jsonld' schema, so in that case embed the json schema instead of referencing it.

Author: ttskch

src/Hydra/JsonSchema/SchemaFactory.php

@@ -137,8 +137,9 @@ public function buildSchema(string $className, string $format = 'jsonld', string
             $definitionName .= '.input';
         }
 
-        $jsonSchema = $this->schemaFactory->buildSchema($className, 'json', $type, $operation, null, $serializerContext, $forceCollection);
+        $jsonSchema = $this->schemaFactory->buildSchema($className, 'json', $type, $operation, new Schema(version: $schema->getVersion()), $serializerContext, $forceCollection);
         $jsonKey = $jsonSchema->getRootDefinitionKey() ?? $jsonSchema->getItemsDefinitionKey();
+        $jsonDefinition = $jsonSchema->getDefinitions()[$jsonKey] ?? null;
 
         if (!$collectionKey) {
             $schema['$ref'] = $prefix.$definitionName;
@@ -160,6 +161,11 @@ public function buildSchema(string $className, string $format = 'jsonld', string
                 ['$ref' => $prefix.$jsonKey],
             ]]);
 
+            // ensure the JSON format definition is present
+            if (!isset($definitions[$jsonKey])) {
+                $definitions[$jsonKey] = $jsonDefinition;
+            }
+
             if (isset($definitions[$jsonKey]['description'])) {
                 $allOf['description'] = $definitions[$jsonKey]['description'];
             }