[mob][photos] Lower cluster size threshold on discover page (#7105)

## Description

Lower cluster size threshold on discover page

mobile/apps/photos/lib/models/search/search_types.dart

@@ -14,6 +14,7 @@ import "package:photos/models/collection/collection_items.dart";
 import "package:photos/models/search/search_result.dart";
 import "package:photos/models/typedefs.dart";
 import "package:photos/services/collections_service.dart";
+import "package:photos/services/machine_learning/face_ml/face_filtering/face_filtering_constants.dart";
 import "package:photos/services/search_service.dart";
 import "package:photos/ui/viewer/gallery/collection_page.dart";
 import "package:photos/ui/viewer/location/add_location_sheet.dart";
@@ -220,7 +221,12 @@ extension SectionTypeExtensions on SectionType {
   }) {
     switch (this) {
       case SectionType.face:
-        return SearchService.instance.getAllFace(limit);
+        return SearchService.instance.getAllFace(
+          limit,
+          minClusterSize: limit == null
+              ? kMinimumClusterSizeAllFaces
+              : kMinimumClusterSizeSearchResult,
+        );
       case SectionType.magic:
         return SearchService.instance.getMagicSectionResults(context!);
       case SectionType.location:

mobile/apps/photos/lib/services/search_service.dart

@@ -46,7 +46,6 @@ import 'package:photos/services/collections_service.dart';
 import "package:photos/services/date_parse_service.dart";
 import "package:photos/services/filter/db_filters.dart";
 import "package:photos/services/location_service.dart";
-import "package:photos/services/machine_learning/face_ml/face_filtering/face_filtering_constants.dart";
 import "package:photos/services/machine_learning/face_ml/person/person_service.dart";
 import 'package:photos/services/machine_learning/semantic_search/semantic_search_service.dart';
 import "package:photos/services/memories_cache_service.dart";
@@ -725,7 +724,7 @@ class SearchService {
 
   Future<List<GenericSearchResult>> getAllFace(
     int? limit, {
-    int minClusterSize = kMinimumClusterSizeSearchResult,
+    required int minClusterSize,
   }) async {
     try {
       debugPrint("getting faces");
@@ -894,13 +893,7 @@ class SearchService {
           ),
         );
       }
-      if (facesResult.isEmpty) {
-        if (kMinimumClusterSizeAllFaces < minClusterSize) {
-          return getAllFace(limit, minClusterSize: kMinimumClusterSizeAllFaces);
-        } else {
-          return [];
-        }
-      }
+      if (facesResult.isEmpty) return [];
       if (limit != null) {
         return facesResult.sublist(0, min(limit, facesResult.length));
       } else {

mobile/apps/photos/lib/ui/viewer/search/search_widget.dart

@@ -252,7 +252,7 @@ class SearchWidgetState extends State<SearchWidget> {
       },
     );
 
-    _searchService.getAllFace(null).then(
+    _searchService.getAllFace(null, minClusterSize: 10).then(
       (faceResult) {
         final List<GenericSearchResult> filteredResults = [];
         for (final result in faceResult) {