FIX: accounts for hide_profile_and_presence core user option (#20991)

Chat will now correctly use this core setting and will not show the presence of the user in this case.

plugins/chat/spec/system/user_presence.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+RSpec.describe "User presence", type: :system, js: true do
+  fab!(:channel_1) { Fabricate(:chat_channel) }
+  fab!(:current_user) { Fabricate(:user) }
+
+  let(:channel) { PageObjects::Pages::ChatChannel.new }
+
+  before do
+    chat_system_bootstrap
+    channel_1.add(current_user)
+  end
+
+  it "shows presence indicator" do
+    sign_in(current_user)
+    chat.visit_channel(channel_1)
+    channel.send_message("Am I present?")
+
+    expect(page).to have_selector(".chat-user-avatar.is-online")
+  end
+
+  context "when user hides presence" do
+    it "hides the presence indicator" do
+      current_user.user_option.update!(hide_profile_and_presence: true)
+      sign_in(current_user)
+      chat.visit_channel(channel_1)
+      channel.send_message("Am I present?")
+
+      expect(page).to have_no_selector(".chat-user-avatar.is-online")
+    end
+  end
+end