Move COLORS and c() to BBS::Color in rubbs

include BBS::Color at top level — c() available everywhere
including instance_eval blocks and OutputBuilder.

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

bbs.rb

@@ -7,21 +7,13 @@ require_relative 'lib/repository/message_board_repository'
 require_relative 'lib/repository/wiki_repository'
 require_relative 'lib/repository/catalog_repository'
 
+include BBS::Color
+
 ONLINE   = OnlineUsersRepository.new
 MESSAGES = MessageBoardRepository.new(ENV.fetch('MESSAGES_PATH', 'data/messages.dat'))
 WIKI     = WikiRepository.new(token: ENV['WEBAPP_WIKIJS_TOKEN'])
 CATALOG  = CatalogRepository.new
 
-COLORS = {
-  reset: "\e[0m",    gray:    "\e[0;37m", yellow:  "\e[0;33m",
-  white: "\e[1;37m", blue:    "\e[0;34m", cyan:    "\e[0;36m",
-  green: "\e[1;32m", magenta: "\e[0;35m", red:     "\e[1;31m"
-}.freeze
-
-def c(color, text)
-  "#{COLORS.fetch(color)}#{text}#{COLORS[:reset]}"
-end
-
 class OutputBuilder
   def initialize = (@buf = +''; @badges = [])
   def to_s       = (flush_badges; @buf)
@@ -52,8 +44,6 @@ class OutputBuilder
 
   private
 
-  def c(color, text) = "#{COLORS.fetch(color)}#{text}#{COLORS[:reset]}"
-
   def flush_badges
     return if @badges.empty?
     @buf << "  #{@badges.join('  ')}\r\n"