Refactor gRPC adapter to use connection pool and improve error handling in product retrieval

internal/ozon/rate_limiter.go

@@ -43,7 +43,6 @@ type RateLimitTransport struct {
 }
 
 func (t *RateLimitTransport) RoundTrip(req *http.Request) (*http.Response, error) {
-	fmt.Println(time.Now().Format("2006-01-02 15:04:05"))
 	ctx := req.Context()
 	clientId := req.Header.Get("Client-Id")
 	now := time.Now().UnixNano()
@@ -57,6 +56,7 @@ func (t *RateLimitTransport) RoundTrip(req *http.Request) (*http.Response, error
 		return nil, fmt.Errorf("failed to execute rate limit script: %w", err)
 	}
 	if waitTime > 0 {
+		fmt.Printf("Rate limit exceeded for client %s, waiting for %d nanoseconds\n", clientId, waitTime)
 		time.Sleep(time.Duration(waitTime))
 	}
 	return t.RoundTripper.RoundTrip(req)