fix: addon-scope static CRT (Windows/Max) + complete ui in the class header

- Set CMAKE_MSVC_RUNTIME_LIBRARY at the top of the addon so the object
  library and every back-end external share the /MT runtime the Max
  external needs (mixing /MT and /MD trips MSVC LNK2038).
- Include UI.hpp from the class header so <Class>::ui is a complete type
  for the score plugin generator (it includes the class header, not the
  MAIN_FILE, and needs the full ui to build the process layer).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: jcelerier

CMakeLists.txt

@@ -2,6 +2,14 @@ cmake_minimum_required(VERSION 3.24 FATAL_ERROR)
 
 project(MyProcessor CXX)
 
+# Max/MSP externals link the static CRT (/MT) on Windows, as the official
+# max-sdk-base requires. Set it for the whole addon -- before Avendish and the
+# object library are created -- so every target shares one runtime; mixing /MT
+# and /MD trips MSVC with LNK2038. (CMP0091 is NEW via cmake_minimum_required.)
+if(MSVC)
+  set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
+endif()
+
 # Use the Avendish the host already provides (e.g. ossia score); otherwise fetch it.
 # The same CMakeLists builds this as an ossia/score add-on or as a standalone object.
 find_package(Avendish QUIET)

src/Model.hpp

@@ -54,3 +54,8 @@ inline void MyProcessor::operator()(int N)
     }
   }
 }
+
+// Pull in the UI so MyProcessor::ui is complete wherever this class header is
+// included -- the score plugin generator includes the class header, not the
+// MAIN_FILE, and needs the full ui type to build the process's layer.
+#include "UI.hpp"