feat(ee): Add a service to fetch website content and prepare a persona of Captain Assistant (#12732)

This PR is the first of many to simplify the process of building an
assistant. The new flow will only require the user’s website. We’ll
automatically crawl it, identify the business name and what the business
does, and then generate a suggested assistant persona, complete with a
proposed name and description.

This service returns the following.
Example: tooljet.com
<img width="795" height="217" alt="Screenshot 2025-10-25 at 2 55 04 PM"
src="https://github.com/user-attachments/assets/9cb3594a-9c9c-4970-a0a1-4c9c8869c193"
/>

Example: replit.com
<img width="797" height="176" alt="Screenshot 2025-10-25 at 2 56 42 PM"
src="https://github.com/user-attachments/assets/6a1b4266-aab6-455f-a5e3-696d3a8243c9"
/>

enterprise/app/services/captain/tools/simple_page_crawl_service.rb

@@ -19,6 +19,20 @@ class Captain::Tools::SimplePageCrawlService
     ReverseMarkdown.convert @doc.at_xpath('//body'), unknown_tags: :bypass, github_flavored: true
   end
 
+  def meta_description
+    meta_desc = @doc.at_css('meta[name="description"]')
+    return nil unless meta_desc && meta_desc['content']
+
+    meta_desc['content'].strip
+  end
+
+  def favicon_url
+    favicon_link = @doc.at_css('link[rel*="icon"]')
+    return nil unless favicon_link && favicon_link['href']
+
+    resolve_url(favicon_link['href'])
+  end
+
   private
 
   def sitemap?
@@ -35,4 +49,12 @@ class Captain::Tools::SimplePageCrawlService
       absolute_url
     end
   end
+
+  def resolve_url(url)
+    return url if url.start_with?('http')
+
+    URI.join(@external_link, url).to_s
+  rescue StandardError
+    url
+  end
 end