Fix type-checking errors in snippets (code only, no .md)

This commit both:
- Fixes pre-existing mistakes in snippets, aka wrong code samples.
- Adds hidden (`@hide`) statements that do not appear in the docs,
  but satisfy typecheckers.

qdrant-landing/content/documentation/headless/snippets/inference/openai-query/go.go

@@ -2,7 +2,6 @@ package snippet
 
 import (
 	"context"
-	"time"
 
 	"github.com/qdrant/go-client/qdrant"
 )
@@ -15,7 +14,9 @@ func Main() {
 		UseTLS: true,
 	})
 
-	client.Query(ctx, &qdrant.QueryPoints{
+	if err != nil { panic(err) } // @hide
+
+	client.Query(context.Background(), &qdrant.QueryPoints{
 		CollectionName: "{collection_name}",
 		Query: qdrant.NewQueryNearest(
 			qdrant.NewVectorInputDocument(&qdrant.Document{

qdrant-landing/content/documentation/headless/snippets/inference/openai-query/java.java

@@ -6,6 +6,7 @@ import static io.qdrant.client.ValueFactory.value;
 import io.qdrant.client.QdrantClient;
 import io.qdrant.client.QdrantGrpcClient;
 import io.qdrant.client.grpc.Points.Document;
+import io.qdrant.client.grpc.Points.QueryPoints;
 import java.util.Map;
 
 public class Snippet {
@@ -17,7 +18,7 @@ public class Snippet {
                             .build());
                 client
                     .queryAsync(
-                        Points.QueryPoints.newBuilder()
+                        QueryPoints.newBuilder()
                             .setCollectionName("{collection_name}")
                             .setQuery(
                                 nearest(

qdrant-landing/content/documentation/headless/snippets/inference/openai-query/rust.rs

@@ -1,5 +1,5 @@
 use qdrant_client::{
-    Qdrant, QdrantError,
+    Qdrant,
     qdrant::{Document, Query, QueryPointsBuilder, Value},
 };
 use std::collections::HashMap;