DEV: Deprecate Site.mobileView/desktopView during initialization (#34122)

This commit introduces deprecation warnings for accessing Site.mobileView or
Site.desktopView during application initialization to prevent
layout-related errors and improve code reliability.

The changes include:

* Added deprecation warnings for Site.mobileView and Site.desktopView
access during the initialization phase.
* Updated multiple plugins and components to avoid these deprecated
calls during startup.
* Refactored initialization logic across discourse-ai, discourse-chat,
discourse-calendar, discourse-reactions, discourse-assign,
discourse-subscriptions, and discourse-user-notes plugins
* Improved error prevention by discouraging early access to
view-dependent properties before the application is fully initialized
* Enhanced code maintainability by establishing clearer boundaries
between initialization and runtime phases

This deprecation helps prevent subtle bugs that can occur when
components try to determine the view type before the application context
is properly established, leading to more robust plugin initialization
patterns.

plugins/chat/test/javascripts/acceptance/chat-channel-reactions-test.js

@@ -21,7 +21,7 @@ const message = {
 
 acceptance("Discourse Chat - Channel Reactions", function (needs) {
   needs.user({ has_chat_enabled: true });
-  needs.settings({ chat_enabled: true });
+  needs.settings({ chat_enabled: true, enable_emoji: true });
 
   needs.hooks.beforeEach(function () {
     pretender.get("/chat/api/me/channels", () =>

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

@@ -19,7 +19,11 @@ const GROUP_NAME = "group1";
 
 acceptance("Discourse Chat - Composer", function (needs) {
   needs.user({ has_chat_enabled: true });
-  needs.settings({ chat_enabled: true, enable_rich_text_paste: true });
+  needs.settings({
+    chat_enabled: true,
+    enable_rich_text_paste: true,
+    enable_emoji: true,
+  });
   needs.pretender((server, helper) => {
     baseChatPretenders(server, helper);
     chatChannelPretender(server, helper);
@@ -70,7 +74,10 @@ acceptance("Discourse Chat - Composer", function (needs) {
 let sendAttempt = 0;
 acceptance("Discourse Chat - Composer - unreliable network", function (needs) {
   needs.user({ id: 1, has_chat_enabled: true });
-  needs.settings({ chat_enabled: true });
+  needs.settings({
+    chat_enabled: true,
+    enable_emoji: true,
+  });
   needs.pretender((server, helper) => {
     chatChannelPretender(server, helper);
     server.get("/chat/:id/messages.json", () =>

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

@@ -12,6 +12,7 @@ acceptance("Discourse Chat - Chat live pane collapse", function (needs) {
 
   needs.settings({
     chat_enabled: true,
+    enable_emoji: true,
   });
 
   needs.pretender((server, helper) => {

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

@@ -13,6 +13,7 @@ acceptance(
     needs.settings({
       chat_enabled: true,
       navigation_menu: "legacy",
+      enable_emoji: true,
     });
 
     needs.pretender((server, helper) => {

plugins/chat/test/javascripts/acceptance/hashtag-css-generator-test.js

@@ -23,7 +23,10 @@ acceptance("Chat | Hashtag CSS Generator", function (needs) {
     name: "category3",
   };
 
-  needs.settings({ chat_enabled: true });
+  needs.settings({
+    chat_enabled: true,
+    enable_emoji: true,
+  });
   needs.user({
     has_chat_enabled: true,
   });