FEATURE: created edit and delete flags (#27484)

Allow admins to create edit and delete flags.

app/serializers/post_action_type_serializer.rb

@@ -10,6 +10,8 @@ class PostActionTypeSerializer < ApplicationSerializer
     :is_flag,
     :is_custom_flag,
     :enabled,
+    :applies_to,
+    :is_used,
   )
 
   include ConfigurableUrls
@@ -27,7 +29,14 @@ class PostActionTypeSerializer < ApplicationSerializer
   end
 
   def description
-    i18n("description", vars: { tos_url:, base_path: Discourse.base_path })
+    i18n(
+      "description",
+      vars: {
+        tos_url:,
+        base_path: Discourse.base_path,
+      },
+      default: object.class.descriptions[object.id],
+    )
   end
 
   def short_description
@@ -42,6 +51,15 @@ class PostActionTypeSerializer < ApplicationSerializer
     !!PostActionType.enabled_flag_types[object.id]
   end
 
+  def applies_to
+    Array.wrap(PostActionType.applies_to[object.id])
+  end
+
+  def is_used
+    PostAction.exists?(post_action_type_id: object.id) ||
+      ReviewableScore.exists?(reviewable_score_type: object.id)
+  end
+
   protected
 
   def i18n(field, default: nil, vars: nil)

app/serializers/reviewable_score_type_serializer.rb

@@ -10,8 +10,7 @@ class ReviewableScoreTypeSerializer < ApplicationSerializer
   # Allow us to share post action type translations for backwards compatibility
   def title
     I18n.t("post_action_types.#{type}.title", default: nil) ||
-      I18n.t("reviewable_score_types.#{type}.title", default: nil) ||
-      PostActionType.flag_settings.names[id]
+      I18n.t("reviewable_score_types.#{type}.title", default: nil) || PostActionType.names[id]
   end
 
   def reviewable_priority

app/serializers/site_serializer.rb

@@ -48,6 +48,7 @@ class SiteSerializer < ApplicationSerializer
     :privacy_policy_url,
     :system_user_avatar_template,
     :lazy_load_categories,
+    :valid_flag_applies_to_types,
   )
 
   has_many :archetypes, embed: :objects, serializer: ArchetypeSerializer
@@ -350,6 +351,14 @@ class SiteSerializer < ApplicationSerializer
     scope.can_lazy_load_categories?
   end
 
+  def valid_flag_applies_to_types
+    Flag.valid_applies_to_types
+  end
+
+  def include_valid_flag_applies_to_types?
+    scope.is_admin?
+  end
+
   private
 
   def ordered_flags(flags)