Bump macOS to version 26 (#373)

- Linked Case: NOJIRAID

### Description

Was trying to build sketcher on macos (M4). Hit this error:
```
In file included from /Users/runner/work/sketcher/sketcher/build/external/qt-prefix/src/qt-build/qtbase/include/QtCore/qyieldcpu.h:1:
/Users/runner/work/sketcher/sketcher/build/external/qt-prefix/src/qt/qtbase/src/corelib/thread/qyieldcpu.h:35:5: error: implicitly declaring library function '__yield' with type 'void ()' [-Werror,-Wimplicit-function-declaration]
   35 |     __yield();              // Generic
      |     ^
/Users/runner/work/sketcher/sketcher/build/external/qt-prefix/src/qt/qtbase/src/corelib/thread/qyieldcpu.h:35:5: note: include the header <arm_acle.h> or explicitly provide a declaration for '__yield'
1 error generated.
ninja: build stopped: subcommand failed.
```
also reproducible when I bumped to `macos-26` on CI--did this since the
XCode version reflects what we use for 26.3. Let me know if you dont
want to include the bump to 26 here and just have the patch only.

Claude's explanation:

====

Apple clang 21+ has `__has_builtin(__yield)` as `true`, so Qt 6.x's
qyieldcpu.h takes its generic `__yield()` branch — but `__yield()` is
only declared in <arm_acle.h>, which that header never includes. Qt
compiles with -Werror=implicit-function-declaration, so the implicit
declaration becomes a hard error.

=====

Not sure if this may be addressed/solved with a more recent Qt?

### Testing Done
Tests on macos-26 pass.

Author: JarrettSJohnson

.github/workflows/sketcher-builder.yml

@@ -37,6 +37,7 @@ jobs:
 
   build-test:
     needs: pre-commit
+    name: build-test (${{ matrix.build-name }}, ${{ matrix.runner }})
     runs-on: ${{ matrix.runner }}
     defaults:
       run:
@@ -47,6 +48,10 @@ jobs:
         include:
           - build-name: macos
             runner: macos-15
+            os-label: macos-15
+          - build-name: macos
+            runner: macos-26
+            os-label: macos-26
           - build-name: windows
             runner: windows-2022
           - build-name: ubuntu
@@ -270,7 +275,7 @@ jobs:
         if: always() && steps.sketcher-build.outcome == 'success'
         uses: actions/upload-artifact@v6
         with:
-          name: sketcher-${{ inputs.ref || github.sha }}-${{ matrix.build-name }}
+          name: sketcher-${{ inputs.ref || github.sha }}-${{ matrix.os-label || matrix.build-name }}
           path: |
             build/sketcher_app
             !build/sketcher_app/*.manifest

external/CMakeLists.txt

@@ -295,6 +295,8 @@ ExternalProject_Add(
   GIT_TAG v${QT_VERSION}
   GIT_SUBMODULES ${QT_GIT_SUBMODULES}
   GIT_SHALLOW TRUE
+  PATCH_COMMAND ${CMAKE_COMMAND} -P
+                ${CMAKE_CURRENT_SOURCE_DIR}/qt_yield_acle_patch.cmake
   CMAKE_ARGS
     ${COMMON_EXTERNAL_PROJECT_CMAKE_ARGS}
     -DCMAKE_INSTALL_PREFIX=${CMAKE_CURRENT_BINARY_DIR}/qt-${QT_VERSION}

external/qt_yield_acle_patch.cmake

@@ -0,0 +1,31 @@
+# Inject <arm_acle.h> into qtbase's qyieldcpu.h.
+#
+# Apple clang >= 21 reports __has_builtin(__yield) == true, but __yield() is
+# only declared in <arm_acle.h>. Without that include the generic branch of
+# qYieldCpu() implicitly-declares the function and the Qt build fails under
+# -Werror=implicit-function-declaration. Run as a PATCH_COMMAND from the Qt
+# source root; idempotent so re-running is harmless.
+
+set(_file "qtbase/src/corelib/thread/qyieldcpu.h")
+
+if(NOT EXISTS "${_file}")
+  message(STATUS "qt_yield_acle_patch: ${_file} not found, skipping")
+  return()
+endif()
+
+file(READ "${_file}" _contents)
+
+if(_contents MATCHES "arm_acle.h")
+  message(STATUS "qt_yield_acle_patch: already applied")
+  return()
+endif()
+
+string(
+  REPLACE
+    "#include <QtCore/qtconfigmacros.h>"
+    "#include <QtCore/qtconfigmacros.h>\n\n#if defined(__has_include)\n#  if defined(__ARM_ACLE) && __has_include(<arm_acle.h>)\n#    include <arm_acle.h>\n#  endif\n#endif"
+    _contents
+    "${_contents}")
+
+file(WRITE "${_file}" "${_contents}")
+message(STATUS "qt_yield_acle_patch: applied to ${_file}")