DEV: Correct some tl to group site setting changes (#25550)

- Created a new migration for here_mention
- Updated existing migration for here_mention
- Updated site settings for here_mention, create_tag, and
  send_email_messages

db/migrate/20231107055903_migrate_min_trust_level_for_here_mention_to_group.rb

@@ -15,17 +15,10 @@ class MigrateMinTrustLevelForHereMentionToGroup < ActiveRecord::Migration[7.0]
         when "admin"
           "1"
         when "staff"
-          "3"
-        when "0"
-          "10"
-        when "1"
-          "11"
-        when "2"
-          "12"
-        when "3"
-          "13"
-        when "4"
-          "14"
+          "1|3"
+          # Matches Group::AUTO_GROUPS to the trust levels.
+        else
+          "1|3|1#{min_trust_level_for_here_mention_raw}"
         end
 
       # Data_type 20 is group_list.

db/migrate/20240202204030_fix_here_mention_allowed_groups_setting.rb

@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+class FixHereMentionAllowedGroupsSetting < ActiveRecord::Migration[7.0]
+  def up
+    configured_trust_level =
+      DB.query_single(
+        "SELECT value FROM site_settings WHERE name = 'min_trust_level_for_here_mention' LIMIT 1",
+      ).first
+
+    configured_groups =
+      DB.query_single(
+        "SELECT value FROM site_settings WHERE name = 'here_mention_allowed_groups' LIMIT 1",
+      ).first
+
+    # We only need to do anything if it's been changed in the DB.
+    if configured_trust_level.present? && configured_groups.present?
+      # The previous migration for this, changed it to only
+      # `"1#{configured_trust_level}"`, so if it has been
+      # changed we need to add back in admin & staff if they match.
+      if "1#{configured_trust_level}" == configured_groups
+        corresponding_group = "1|3|1#{configured_trust_level}"
+      end
+
+      if corresponding_group
+        DB.exec(
+          "UPDATE site_settings SET value = :setting, updated_at = NOW() WHERE name = 'here_mention_allowed_groups'",
+          setting: corresponding_group,
+        )
+      end
+    end
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end