FIX: Remove broken narrative-bot search context logic (#26319)

In the past we had logic to automatically set the search context to the current topic during the tutorial. This hasn't worked for a long time, and clearly people have still been able to complete the tutorial. In fact, it's probably better for us to teach people how to use the search un-assisted anyway.

This commit removes the dead logic, and makes a slight tweak to the copy in the unlikely event of confusion.

plugins/discourse-narrative-bot/assets/javascripts/initializers/new-user-narrative.js

@@ -1,63 +0,0 @@
-import { withPluginApi } from "discourse/lib/plugin-api";
-import { bind } from "discourse-common/utils/decorators";
-
-export default {
-  name: "new-user-narrative",
-
-  initialize(container) {
-    const siteSettings = container.lookup("service:site-settings");
-
-    if (!siteSettings.discourse_narrative_bot_enabled) {
-      return;
-    }
-
-    this.messageBus = container.lookup("service:message-bus");
-    this.appEvents = container.lookup("service:app-events");
-
-    withPluginApi("0.8.7", (api) => {
-      this.currentUser = api.getCurrentUser();
-
-      if (!this.currentUser) {
-        return;
-      }
-
-      api.dispatchWidgetAppEvent(
-        "site-header",
-        "header",
-        "header:search-context-trigger"
-      );
-
-      api.attachWidgetAction(
-        "header",
-        "headerSearchContextTrigger",
-        function () {
-          if (this.site.mobileView) {
-            this.state.skipSearchContext = false;
-          } else {
-            this.state.contextEnabled = true;
-            this.state.searchContextType = "topic";
-          }
-        }
-      );
-
-      this.messageBus.subscribe(
-        `/new_user_narrative/tutorial_search/${this.currentUser.id}`,
-        this.onMessage
-      );
-    });
-  },
-
-  teardown() {
-    if (this.currentUser) {
-      this.messageBus?.unsubscribe(
-        `/new_user_narrative/tutorial_search/${this.currentUser.id}`,
-        this.onMessage
-      );
-    }
-  },
-
-  @bind
-  onMessage() {
-    this.appEvents.trigger("header:search-context-trigger");
-  },
-};

plugins/discourse-narrative-bot/config/locales/server.en.yml

@@ -314,7 +314,7 @@ en:
 
       search:
         instructions: |-
-          _psst_ … I’ve hidden a surprise in this topic. If you’re up for the challenge, **select the search icon** <img src="%{base_uri}/plugins/discourse-narrative-bot/images/font-awesome-search.png" width="16" height="16"> at the top right &#8599; to search for it.
+          _psst_ … I’ve hidden a surprise in this topic. If you’re up for the challenge, **select the search icon** <img src="%{base_uri}/plugins/discourse-narrative-bot/images/font-awesome-search.png" width="16" height="16"> at the top right &#8599;, choose 'in this topic', then search for it.
 
           Try searching for the term "capy&#8203;bara" in this topic
         hidden_message: |-

plugins/discourse-narrative-bot/lib/discourse_narrative_bot/new_user_narrative.rb

@@ -173,12 +173,6 @@ module DiscourseNarrativeBot
       topic = @post.topic
       post = topic.first_post
 
-      MessageBus.publish(
-        "/new_user_narrative/tutorial_search/#{@user.id}",
-        {},
-        user_ids: [@user.id],
-      )
-
       raw = <<~MD
       #{post.raw}