Phase 0: accessibility mod bootstrap and TTS

Establishes the mod skeleton and gets speech working end to end.

Game-file footprint: one line in main.lua.

- accessibility/init.lua: sole entry point. Patch registry, hooks states.switch
  (announces screen changes) and states.update (per-frame speech flush, avoiding
  an edit to love.update). Startup self-test prints what resolved -- the canary
  for when a future game version moves something we hook.
- accessibility/speech.lua: TTS wrapper. pcall-guarded so a missing DLL degrades
  to silence instead of crashing. Queues utterances within a frame and joins them,
  since one game turn emits several console.print calls and speaking each with
  interrupt would leave only the last audible.
- accessibility/stateNames.lua: spoken names for the 28 states.
- accessibility/vendor/love2talk: vendored TTS library, see VENDORED.md.
  Loads Tolk.dll by absolute path via love.filesystem.getSource() and adds that
  directory via SetDllDirectory, so the DLLs live in the project instead of
  needing an elevated copy into Program Files.

Verified with lovec against NVDA: TTS available, speech channel yes,
'Main menu' spoken on startup.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

accessibility/vendor/love2talk/Love2talk.lua

@@ -0,0 +1,51 @@
+-- love2talk — vendored from d:\code\love2talk
+-- See VENDORED.md for the list of local modifications.
+
+local os = love.system.getOS()
+
+local backend -- upstream leaked this as a global; scoped to the module here
+
+if os == "Windows" then
+	backend = require "accessibility.vendor.love2talk.tolk"
+	backend.trySAPI(true)
+elseif os == "OS X" then
+	backend = require "accessibility.vendor.love2talk.macspeech"
+end
+
+local function say(text, interrupt)
+	if not backend then
+		return
+	end
+	interrupt = interrupt or false
+	if os == "Windows" then
+		backend.output(text, interrupt)
+	else
+		backend.output(text)
+	end
+end
+
+local function isSpeaking()
+	if not backend then
+		return false
+	end
+	return backend.isSpeaking()
+end
+
+local function silence()
+	if not backend or not backend.silence then
+		return
+	end
+	backend.silence()
+end
+
+-- LOCAL ADDITION: exposed for diagnostics. Tells us whether Tolk actually found a
+-- speech channel (a running screen reader, or the SAPI fallback) as opposed to
+-- merely having loaded the DLL successfully.
+local function hasSpeech()
+	if not backend or not backend.hasSpeech then
+		return false
+	end
+	return backend.hasSpeech()
+end
+
+return {say = say, isSpeaking = isSpeaking, silence = silence, hasSpeech = hasSpeech}