FEATURE: Support designating multiple groups as mods on category (#28655)

Currently, categories support designating only 1 group as a moderation group on the category. This commit removes the one group limitation and makes it possible to designate multiple groups as mods on a category.

Internal topic: t/124648.

app/jobs/regular/notify_reviewable.rb

@@ -20,23 +20,18 @@ class Jobs::NotifyReviewable < ::Jobs::Base
 
           all_updates[:admins][r.id] = payload
           all_updates[:moderators][r.id] = payload if r.reviewable_by_moderator?
-          all_updates[r.reviewable_by_group_id][r.id] = payload if r.reviewable_by_group_id
+
+          if SiteSetting.enable_category_group_moderation? && r.category.present?
+            r
+              .category
+              .moderating_groups
+              .pluck(:id)
+              .each { |group_id| all_updates[group_id][r.id] = payload }
+          end
         end
     end
 
     DistributedMutex.synchronize("notify_reviewable_job", validity: 120) do
-      counts = Hash.new(0)
-      Reviewable
-        .default_visible
-        .pending
-        .group(:reviewable_by_moderator, :reviewable_by_group_id)
-        .pluck(:reviewable_by_moderator, :reviewable_by_group_id, "count(*)")
-        .each do |reviewable_by_moderator, reviewable_by_group_id, count|
-          counts[:admins] += count
-          counts[:moderators] += count if reviewable_by_moderator
-          counts[reviewable_by_group_id] += count if reviewable_by_group_id
-        end
-
       notify_users(User.real.admins, all_updates[:admins])
 
       if reviewable.reviewable_by_moderator?
@@ -46,16 +41,21 @@ class Jobs::NotifyReviewable < ::Jobs::Base
         )
       end
 
-      if SiteSetting.enable_category_group_moderation? && (group = reviewable.reviewable_by_group)
-        users = group.users.includes(:group_users).where("users.id NOT IN (?)", @contacted)
+      if SiteSetting.enable_category_group_moderation? && reviewable.category.present?
+        users =
+          User
+            .includes(:group_users)
+            .joins(:group_users)
+            .joins(
+              "INNER JOIN category_moderation_groups ON category_moderation_groups.group_id = group_users.group_id",
+            )
+            .where("category_moderation_groups.category_id": reviewable.category.id)
+            .where("users.id NOT IN (?)", @contacted)
+            .distinct
 
         users.find_each do |user|
-          count = 0
           updates = {}
-          user.group_users.each do |gu|
-            updates.merge!(all_updates[gu.group_id])
-            count += counts[gu.group_id]
-          end
+          user.group_users.each { |gu| updates.merge!(all_updates[gu.group_id]) }
 
           notify_user(user, updates)
         end