vendor: 引入 Lua 3.2 官方源码 + 移植评估 (lua_3.2 分支)

- 前 lua_State 时代 API(全局单例状态机), 与项目多实例+管道模式抽象冲突
- 评估结论: 不建议移植, 详见 doc/ADAPTATION-lua32.md

lib/lua/COPYRIGHT

@@ -0,0 +1,51 @@
+Lua COPYRIGHT NOTICE
+--------------------
+
+Lua is free and non-proprietary.
+It can be used for both academic and commercial purposes at absolutely no cost.
+There are no royalties or GNU-like "copyleft" restrictions.
+Lua (probably) qualifies as Open Source software.
+Nevertheless, Lua is not in the public domain and TeCGraf keeps its copyright. 
+
+If you use Lua, please give us credit (a nice way to do this is to include a
+logo in a web page for your product), but we would appreciate *not* receiving
+lengthy legal documents to sign.
+
+The legal details are below. 
+
+===============================================================================
+
+Copyright (c) 1994-1999 TeCGraf, PUC-Rio.  All rights reserved.
+
+Permission is hereby granted, without written agreement and without license
+or royalty fees, to use, copy, modify, and distribute this software and its
+documentation for any purpose, including commercial applications, subject to
+the following conditions:
+
+ * The above copyright notice and this permission notice shall appear in all
+   copies or substantial portions of this software.
+
+ * The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software in a
+   product, an acknowledgment in the product documentation would be greatly
+   appreciated (but it is not required).
+
+ * Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+   
+The authors specifically disclaim any warranties, including, but not limited
+to, the implied warranties of merchantability and fitness for a particular
+purpose.  The software provided hereunder is on an "as is" basis, and the
+authors have no obligation to provide maintenance, support, updates,
+enhancements, or modifications.  In no event shall TeCGraf, PUC-Rio, or the
+authors be held liable to any party for direct, indirect, special,
+incidental, or consequential damages arising out of the use of this software
+and its documentation.
+
+The Lua language and this implementation have been entirely designed and written
+by Waldemar Celes, Roberto Ierusalimschy, and Luiz Henrique de Figueiredo
+at TeCGraf, PUC-Rio.
+
+This implementation contains no third-party code.
+
+===============================================================================