Initial SERMO-BBS: a telnet PC that boots SERMO-DOS

A rubbs-based telnet server that drops every caller into a simulated PC:
it POSTs, boots, loads SERMO-DOS, and lands at a C:\> prompt. Built-in DOS
commands (VER/DATE/TIME/ECHO/MEM/DIR/CLS/HELP/EXIT) behave; anything else
is routed to Sermo::Oracle as a question — the hook for a future LLM.

Built on rubbs' configurable BBS::FakeOS engine; the whole OS lives in
lib/sermo/dos.rb as a FakeOS.define block, so new character-mode OSes are
added as config files, not engine changes.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

sermo.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require 'bbs'
+require_relative 'lib/sermo/dos'
+
+# SERMO-BBS — a telnet server that drops every caller into a simulated PC:
+# it boots, loads SERMO-DOS, and leaves you at a C:\> prompt you can talk to.
+BBS.configure do |config|
+  config.port         = (ENV['BBS_PORT'] || 2323).to_i
+  config.mouse        = false
+  config.idle_seconds = (ENV['BBS_IDLE'] || 900).to_i
+end
+
+# A caller's whole session is just the simulated machine.
+BBS.config.flow = BBS::Flow.define do
+  os Sermo::DOS
+end
+
+BBS.start