Refactor recommendation response handling and enhance enrichment logic

- Removed the `buildRecommendedTenderResponsesParallel` method and replaced it with `buildRecommendedTenderListResponses`, simplifying the response building process.
- Introduced `enrichRecommendedTenderResponsesParallel` to handle enrichment of tender responses in parallel, improving performance.
- Updated the `Recommend` method to utilize the new enrichment logic, ensuring timely and efficient processing of recommendations.
- Cleaned up unused functions and imports in `recommendation_page_cache.go` and `recommendation_response.go`, enhancing code clarity and maintainability.

This update streamlines the recommendation response handling and improves the overall efficiency of the tender recommendation service.

internal/tender/recommendation_response.go

@@ -6,6 +6,9 @@ import (
 	"strings"
 	"sync"
 
+	"go.mongodb.org/mongo-driver/v2/bson"
+	"golang.org/x/sync/errgroup"
+
 	"tm/pkg/ai_summarizer"
 )
 
@@ -68,6 +71,72 @@ func (s *tenderService) buildRecommendedTenderListResponses(items []rankedRecomm
 	return out
 }
 
+func (s *tenderService) enrichRecommendedTenderResponsesParallel(ctx context.Context, responses []TenderResponse, language string) []TenderResponse {
+	if len(responses) == 0 || s.aiSummarizerStorage == nil {
+		return responses
+	}
+
+	out := make([]TenderResponse, len(responses))
+	if len(responses) == 1 {
+		out[0] = s.enrichRecommendedTenderResponse(ctx, responses[0], language, newRecommendationTranslationCache())
+		return out
+	}
+
+	translationCache := newRecommendationTranslationCache()
+	group, groupCtx := errgroup.WithContext(ctx)
+	group.SetLimit(recommendationPageCacheConcurrency)
+
+	for i := range responses {
+		i := i
+		group.Go(func() error {
+			out[i] = s.enrichRecommendedTenderResponse(groupCtx, responses[i], language, translationCache)
+			return nil
+		})
+	}
+
+	if err := group.Wait(); err != nil {
+		for i, resp := range responses {
+			out[i] = s.enrichRecommendedTenderResponse(ctx, resp, language, translationCache)
+		}
+	}
+
+	return out
+}
+
+func (s *tenderService) enrichRecommendedTenderResponse(
+	ctx context.Context,
+	resp TenderResponse,
+	language string,
+	cache *recommendationTranslationCache,
+) TenderResponse {
+	enriched := resp
+	tender := tenderFromRecommendationResponse(resp)
+	s.enrichWithTranslationTimeout(
+		ctx,
+		&tender,
+		&enriched,
+		language,
+		cache,
+		recommendTranslationEnrichmentTimeout,
+	)
+	return enriched
+}
+
+func tenderFromRecommendationResponse(item TenderResponse) Tender {
+	var tender Tender
+	if id, err := bson.ObjectIDFromHex(strings.TrimSpace(item.ID)); err == nil {
+		tender.ID = id
+	}
+	tender.ContractFolderID = item.ContractFolderID
+	tender.NoticePublicationID = item.NoticePublicationID
+	tender.RelatedNoticePublicationIDs = append([]string(nil), item.RelatedNoticePublicationIDs...)
+	tender.Status = item.Status
+	tender.PublicationDate = item.PublicationDate
+	tender.SubmissionDeadline = item.SubmissionDeadline
+	tender.TenderDeadline = item.TenderDeadline
+	return tender
+}
+
 func (s *tenderService) loadRecommendationExclusions(
 	ctx context.Context,
 	form *SearchForm,