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/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 pitermach
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.