Introduce model/ and repository/ structure under lib/

Models: Message, WikiPage, Game (typed structs instead of raw hashes)
Repositories: MessageBoard, OnlineUsers, WikiClient, CatalogClient
bbs.rb uses attribute access (page.title, game.play_path, …) throughout

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/repository/wiki.rb

@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+require 'net/http'
+require 'json'
+require 'uri'
+require_relative '../model/wiki_page'
+
+class WikiClient
+  BASE_URL = 'https://wiki.teletype.hu'
+
+  def initialize(token: nil)
+    @token = token
+  end
+
+  def list(tag)
+    query = <<~GQL
+      { pages { list(orderBy: CREATED, orderByDirection: DESC, tags: ["#{tag}"]) {
+        id path title description createdAt locale
+      }}}
+    GQL
+    (graphql(query).dig('data', 'pages', 'list') || []).map do |p|
+      WikiPage.new(
+        id:          p['id'],
+        path:        p['path'],
+        title:       p['title'],
+        description: p['description'],
+        created_at:  p['createdAt'],
+        locale:      p['locale']
+      )
+    end
+  rescue => e
+    warn "Wiki list error: #{e}"
+    []
+  end
+
+  def content(page_id)
+    query = "{ pages { single(id: #{page_id}) { content } } }"
+    graphql(query).dig('data', 'pages', 'single', 'content') || ''
+  rescue => e
+    warn "Wiki content error: #{e}"
+    ''
+  end
+
+  def page_url(locale, path)
+    "#{BASE_URL}/#{locale}/#{path}"
+  end
+
+  private
+
+  def graphql(query)
+    uri  = URI("#{BASE_URL}/graphql")
+    http = Net::HTTP.new(uri.host, uri.port)
+    http.use_ssl       = uri.scheme == 'https'
+    http.open_timeout  = 12
+    http.read_timeout  = 12
+
+    req = Net::HTTP::Post.new(uri.path, 'Content-Type' => 'application/json')
+    req['Authorization'] = "Bearer #{@token}" if @token
+    req.body = JSON.generate(query: query)
+
+    JSON.parse(http.request(req).body)
+  end
+end