Support "Hybrid" parameter in IndexSearchRequest to enable multi search with hybrid search

src/main/java/com/meilisearch/sdk/IndexSearchRequest.java

@@ -1,5 +1,6 @@
 package com.meilisearch.sdk;
 
+import com.meilisearch.sdk.model.Hybrid;
 import com.meilisearch.sdk.model.MatchingStrategy;
 import lombok.*;
 import lombok.experimental.Accessors;
@@ -38,6 +39,7 @@ public class IndexSearchRequest {
     private FederationOptions federationOptions;
     protected String[] locales;
     protected String distinct;
+    protected Hybrid hybrid;
     protected Boolean retrieveVectors;
 
     /**
@@ -110,6 +112,10 @@ public String toString() {
                         .putOpt("distinct", this.distinct)
                         .putOpt("retrieveVectors", this.retrieveVectors);
 
+        if (this.hybrid != null) {
+            jsonObject.put("hybrid", this.hybrid.toJSONObject());
+        }
+
         return jsonObject.toString();
     }
 }

src/test/java/com/meilisearch/sdk/IndexSearchRequestTest.java

@@ -0,0 +1,57 @@
+package com.meilisearch.sdk;
+
+import com.meilisearch.sdk.model.Hybrid;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.is;
+
+class IndexIndexSearchRequestTest {
+    @Test
+    void toStringWithHybridUsingBuilder() {
+        IndexSearchRequest classToTest =
+            IndexSearchRequest.builder()
+                .q("This is a Test")
+                .hybrid(Hybrid.builder().semanticRatio(0.5).embedder("default").build())
+                .build();
+
+        String expected =
+            "{\"q\":\"This is a Test\",\"hybrid\":{\"semanticRatio\":0.5,\"embedder\":\"default\"}}";
+        assertThat(classToTest.toString(), is(equalTo(expected)));
+
+        // Verify getters
+        assertThat(classToTest.getHybrid().getSemanticRatio(), is(equalTo(0.5)));
+        assertThat(classToTest.getHybrid().getEmbedder(), is(equalTo("default")));
+    }
+
+    @Test
+    void toStringWithHybridAndOtherParameters() {
+        IndexSearchRequest classToTest =
+            IndexSearchRequest.builder()
+                .q("This is a Test")
+                .offset(200)
+                .limit(900)
+                .hybrid(
+                    Hybrid.builder()
+                        .semanticRatio(0.7)
+                        .embedder("custom-embedder")
+                        .build())
+                .build();
+
+        String expected =
+            "{\"q\":\"This is a Test\",\"hybrid\":{\"semanticRatio\":0.7,\"embedder\":\"custom-embedder\"},\"offset\":200,\"limit\":900}";
+        assertThat(classToTest.toString(), is(equalTo(expected)));
+    }
+
+    @Test
+    void toStringWithHybridOnlyEmbedder() {
+        IndexSearchRequest classToTest =
+            new IndexSearchRequest("someIndexUuid")
+                .setQuery("This is a Test")
+                .setHybrid(Hybrid.builder().embedder("default").build());
+
+        String expected = "{\"q\":\"This is a Test\",\"hybrid\":{\"embedder\":\"default\"}}";
+        assertThat(classToTest.toString(), is(equalTo(expected)));
+    }
+}