fix: add reflection hints for Dependency class (#22872)

In previous Flow versions, Dependency class had a toJson method that
created an elemental JsonObject to be sent to the client as JSON.
However, the method has been removed and replaced by Jackson
serialization. This causes wrong JSON serialization in native
executables because reflection is required, but metadata is not stored
for the Dependency class.

This change adds the missing reflection hint for the Dependency class.
It also replaces a useless JSON to string to JSON conversion.

Fixes #22870

Author: mcollovati

flow-server/src/main/java/com/vaadin/flow/server/communication/UidlWriter.java

@@ -33,7 +33,6 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import tools.jackson.core.JacksonException;
 import tools.jackson.databind.JsonNode;
 import tools.jackson.databind.node.ArrayNode;
 import tools.jackson.databind.node.ObjectNode;
@@ -221,15 +220,8 @@ private static void populateDependencies(ObjectNode response,
 
         if (!pendingSendToClient.isEmpty()) {
             groupDependenciesByLoadMode(pendingSendToClient, context)
-                    .forEach((loadMode, dependencies) -> {
-                        try {
-                            response.set(loadMode.name(),
-                                    JacksonUtils.getMapper()
-                                            .readTree(dependencies.toString()));
-                        } catch (JacksonException e) {
-                            throw new RuntimeException(e);
-                        }
-                    });
+                    .forEach((loadMode, dependencies) -> response
+                            .set(loadMode.name(), dependencies));
         }
         dependencyList.clearPendingSendToClient();
     }

vaadin-spring/src/main/java/com/vaadin/flow/spring/springnative/VaadinHintsRegistrar.java

@@ -37,6 +37,7 @@
 import com.vaadin.flow.router.internal.DefaultErrorHandler;
 import com.vaadin.flow.server.menu.AvailableViewInfo;
 import com.vaadin.flow.server.menu.RouteParamType;
+import com.vaadin.flow.shared.ui.Dependency;
 
 /**
  * Registers runtime hints for Spring 3 native support.
@@ -134,7 +135,7 @@ private String[] getClasses() {
                 AvailableViewInfo.class.getName(),
                 AvailableViewInfo.DetailDeserializer.class.getName(),
                 AvailableViewInfo.DetailSerializer.class.getName(),
-                RouteParamType.class.getName() };
+                RouteParamType.class.getName(), Dependency.class.getName() };
     }
 
 }