DEV: Pass category/tags to LLM for AI summary (#33861)

This PR passed the category and tags in the request to the LLM for topic
summary, to be leveraged by prompts.

plugins/discourse-ai/lib/summarization/strategies/topic_summary.rb

@@ -41,11 +41,15 @@ module DiscourseAi
         def as_llm_messages(contents)
           resource_path = "#{Discourse.base_path}/t/-/#{target.id}"
           content_title = target.title
+          category_name = target.category&.name
+          tags = target.tags&.map(&:name)&.sort
           input =
             contents.map { |item| "(#{item[:id]} #{item[:poster]} said: #{item[:text]} " }.join
 
           [{ type: :user, content: <<~TEXT.strip }]
             #{content_title.present? ? "The discussion title is: " + content_title + ".\n" : ""}
+            #{category_name.present? ? "Category: " + category_name + ".\n" : ""}
+            #{tags.present? ? "Tags: " + tags.join(", ") + ".\n" : ""}
             Here are the posts, inside <input></input> XML tags:
 
             <input>

plugins/discourse-ai/spec/lib/modules/summarization/strategies/topic_summary_spec.rb

@@ -96,4 +96,59 @@ RSpec.describe DiscourseAi::Summarization::Strategies::TopicSummary do
       end
     end
   end
+
+  describe "#as_llm_messages" do
+    let(:contents) do
+      [{ id: 1, poster: "user1", text: "First post content", last_version_at: Time.now }]
+    end
+
+    it "includes the topic title in the message" do
+      topic.title = "Test Topic Title"
+
+      messages = topic_summary.as_llm_messages(contents)
+      content = messages.first[:content]
+
+      expect(content).to include("The discussion title is: Test Topic Title")
+    end
+
+    context "when topic has a category" do
+      fab!(:category) { Fabricate(:category, name: "Test Category") }
+
+      it "includes the category name in the message" do
+        topic.category = category
+
+        messages = topic_summary.as_llm_messages(contents)
+        content = messages.first[:content]
+
+        expect(content).to include("Category: Test Category")
+      end
+    end
+
+    context "when topic has tags" do
+      fab!(:tag1) { Fabricate(:tag, name: "tag1") }
+      fab!(:tag2) { Fabricate(:tag, name: "tag2") }
+
+      it "includes the tag names in the message" do
+        topic.tags = [tag1, tag2]
+
+        messages = topic_summary.as_llm_messages(contents)
+        content = messages.first[:content]
+
+        expect(content).to include("Tags: tag1, tag2")
+      end
+    end
+
+    context "when topic has no category or tags" do
+      it "doesn't include category or tags in the message" do
+        topic.category = nil
+        topic.tags = []
+
+        messages = topic_summary.as_llm_messages(contents)
+        content = messages.first[:content]
+
+        expect(content).not_to include("Category:")
+        expect(content).not_to include("Tags:")
+      end
+    end
+  end
 end