FEATURE: Chat and Sidebar are now on by default (#19406)

FEATURE: Chat and Sidebar are now on by default

- Set the sidebar site setting to be enabled by default
- Set the chat site setting to be enabled by default
- Updated existing specs that assumed the original default
- Use a migration to keep old defaults for existing sites

plugins/chat/test/javascripts/acceptance/chat-live-pane-silenced-user-test.js

@@ -15,6 +15,7 @@ acceptance("Discourse Chat - Chat live pane", function (needs) {
   });
   needs.settings({
     chat_enabled: true,
+    navigation_menu: "legacy",
   });
   needs.pretender((server, helper) => {
     server.get("/chat/:chatChannelId/messages.json", () =>

plugins/chat/test/javascripts/acceptance/chat-live-pane-test.js

@@ -37,6 +37,7 @@ acceptance(
     });
     needs.settings({
       chat_enabled: true,
+      navigation_menu: "legacy",
     });
 
     let loadAllMessages = false;
@@ -195,6 +196,7 @@ acceptance(
     });
     needs.settings({
       chat_enabled: true,
+      navigation_menu: "legacy",
     });
 
     needs.pretender((server, helper) => {

plugins/chat/test/javascripts/acceptance/chat-status-test.js

@@ -61,6 +61,7 @@ acceptance(
     needs.settings({
       chat_enabled: true,
       chat_allow_archiving_channels: true,
+      navigation_menu: "legacy",
     });
 
     needs.pretender((server, helper) => {