REFACTOR: naming and state refactor (#19187)

- better handling of drawer state using chat state manager
- removes various float and topic occurrences to use drawer
- ensures user can chat before doing a lot of chat setup
- fixes a bug which was creating presence errors in tests
- removes dead code

plugins/chat/spec/system/shortcuts/drawer_spec.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+RSpec.describe "Navigation", type: :system, js: true do
+  fab!(:user_1) { Fabricate(:admin) }
+  fab!(:category_channel_1) { Fabricate(:category_channel) }
+  fab!(:category_channel_2) { Fabricate(:category_channel) }
+  let(:chat_page) { PageObjects::Pages::Chat.new }
+  let(:chat_drawer_page) { PageObjects::Pages::ChatDrawer.new }
+
+  before do
+    chat_system_bootstrap(user_1, [category_channel_1, category_channel_2])
+    sign_in(user_1)
+  end
+
+  context "when drawer is closed" do
+    before { visit("/") }
+
+    context "when pressing dash" do
+      it "opens the drawer" do
+        find("body").send_keys("-")
+
+        expect(page).to have_css(".chat-drawer.is-expanded")
+      end
+    end
+  end
+
+  context "when drawer is opened" do
+    before do
+      visit("/")
+      chat_page.open_from_header
+    end
+
+    context "when pressing escape" do
+      it "opens the drawer" do
+        expect(page).to have_css(".chat-drawer.is-expanded")
+
+        chat_drawer_page.open_channel(category_channel_1)
+        find(".chat-composer-input").send_keys(:escape)
+
+        expect(page).to_not have_css(".chat-drawer.is-expanded")
+      end
+    end
+  end
+end