Add unit tests for tender recommendation translation handling

- Introduced a new test file `recommendation_translation_test.go` to validate the behavior of the tender recommendation service regarding translation handling.
- Implemented tests to ensure that the service correctly applies stored translations and retains original text when no translation is available.
- Enhanced the `Recommend` method in the tender service to utilize a structured approach for managing recommended tenders, improving clarity and maintainability.

This update improves the testing coverage for translation handling in tender recommendations, ensuring accurate responses based on available translations and original content.

internal/tender/service.go

@@ -995,7 +995,13 @@ func (s *tenderService) Recommend(ctx context.Context, form *SearchForm, paginat
 
 	lang := s.pickResponseLanguage(form.Language)
 	now := time.Now().Unix()
-	ordered := make([]TenderResponse, 0, len(recommendations))
+	type rankedRecommendedTender struct {
+		tender    Tender
+		rank      int
+		analysis  string
+		tenderRef string
+	}
+	ordered := make([]rankedRecommendedTender, 0, len(recommendations))
 	for _, rec := range recommendations {
 		tenderRef := strings.TrimSpace(rec.TenderID)
 		tender, ok := tenderByRef[tenderRef]
@@ -1016,11 +1022,12 @@ func (s *tenderService) Recommend(ctx context.Context, form *SearchForm, paginat
 			continue
 		}
 
-		resp := tender.ToResponseWithLanguage(lang)
-		resp.Rank = rec.Rank
-		resp.Analysis = rec.Analysis
-		resp.ProcedureRef = tenderRef
-		ordered = append(ordered, *resp)
+		ordered = append(ordered, rankedRecommendedTender{
+			tender:    tender,
+			rank:      rec.Rank,
+			analysis:  rec.Analysis,
+			tenderRef: tenderRef,
+		})
 	}
 
 	total := int64(len(ordered))
@@ -1033,12 +1040,26 @@ func (s *tenderService) Recommend(ctx context.Context, form *SearchForm, paginat
 		end = len(ordered)
 	}
 
+	paged := make([]TenderResponse, 0, end-start)
+	for _, item := range ordered[start:end] {
+		paged = append(paged, s.buildRecommendedTenderResponse(ctx, item.tender, item.rank, item.analysis, item.tenderRef, lang))
+	}
+
 	return &SearchResponse{
-		Tenders:  ordered[start:end],
+		Tenders:  paged,
 		Metadata: pagination.ListMeta(total, "", end < len(ordered), start),
 	}, nil
 }
 
+func (s *tenderService) buildRecommendedTenderResponse(ctx context.Context, tender Tender, rank int, analysis, tenderRef, language string) TenderResponse {
+	resp := tender.ToResponseWithLanguage(language)
+	s.enrichWithTranslation(ctx, &tender, resp, language)
+	resp.Rank = rank
+	resp.Analysis = analysis
+	resp.ProcedureRef = tenderRef
+	return *resp
+}
+
 func statusAllowed(status TenderStatus, allowed []string) bool {
 	for _, s := range allowed {
 		if string(status) == strings.TrimSpace(s) {