Share a producer base, drop comments and build-script changes

Fold the duplicated IPropertyValue getters and IMarshal tearoff shared by
reference<T> and reference_array<T> into a reference_producer CRTP base; the
two leaves just supply storage, get_as, and create_property_value. Same codegen
and per-instance footprint as the two-template version, ~80 fewer source lines.

Per review feedback, strip the newly-added implementation comments from
base_reference_produce.h and base_string.h, and revert the build_test_all.cmd
compiler-selection helper and its README note so this PR carries only the
projection/boxing functionality.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Author: jonwis

README.md

@@ -13,7 +13,7 @@ Don't build C++/WinRT yourself - just download the latest version here: https://
 
 ## Working on the compiler
 
-If you really want to build it yourself, the simplest way to do so is to run the `build_test_all.cmd` script in the root directory. It takes optional positional arguments: `build_test_all.cmd [platform] [configuration] [version] [clean] [compiler]`, e.g. `build_test_all.cmd x64 Debug 999.999.999.999 "" clang`. The `compiler` argument defaults to `msvc`; pass `clang` (or `clang-cl`) to build the compiler and test projects with the clang-cl toolset, matching the clang-cl leg of CI. Developers needing to work on the C++/WinRT compiler itself should go through the following steps to arrive at an efficient inner loop:
+If you really want to build it yourself, the simplest way to do so is to run the `build_test_all.cmd` script in the root directory. Developers needing to work on the C++/WinRT compiler itself should go through the following steps to arrive at an efficient inner loop:
 
 * Open a dev command prompt pointing at the root of the repo.
 * Open the `cppwinrt.sln` solution.

build_test_all.cmd

@@ -4,43 +4,38 @@ set target_platform=%1
 set target_configuration=%2
 set target_version=%3
 set clean_intermediate_files=%4
-set target_compiler=%5
 
 if "%target_platform%"=="" set target_platform=x64
 if "%target_configuration%"=="" set target_configuration=Release
 if "%target_version%"=="" set target_version=999.999.999.999
-if "%target_compiler%"=="" set target_compiler=msvc
-
-set compiler_props=
-if /i "%target_compiler%"=="clang" set compiler_props=,Clang=1,PlatformToolset=ClangCl
-if /i "%target_compiler%"=="clang-cl" set compiler_props=,Clang=1,PlatformToolset=ClangCl
 
 if not exist ".\.nuget" mkdir ".\.nuget"
 if not exist ".\.nuget\nuget.exe" powershell -Command "$ProgressPreference = 'SilentlyContinue' ; Invoke-WebRequest https://dist.nuget.org/win-x86-commandline/latest/nuget.exe -OutFile .\.nuget\nuget.exe"
 
-call .nuget\nuget.exe restore cppwinrt.sln
+call .nuget\nuget.exe restore cppwinrt.sln"
 call .nuget\nuget.exe restore natvis\cppwinrtvisualizer.sln
 call .nuget\nuget.exe restore test\nuget\NugetTest.sln
 
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:fast_fwd
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:fast_fwd
 
 call msbuild /p:Configuration=%target_configuration%,Platform=%target_platform%,Deployment=Component;CppWinRTBuildVersion=%target_version% natvis\cppwinrtvisualizer.sln
 call msbuild /p:Configuration=%target_configuration%,Platform=%target_platform%,Deployment=Standalone;CppWinRTBuildVersion=%target_version% natvis\cppwinrtvisualizer.sln
 
 if "%target_platform%"=="arm64" goto :eof
 
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:cppwinrt
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:cppwinrt
 
 call msbuild /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% test\nuget\NugetTest.sln
 
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test_nocoro
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test_cpp20
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test_cpp20_no_sourcelocation
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test_fast
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test_slow
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test_module_lock_custom
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\test_module_lock_none
-call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version%%compiler_props% cppwinrt.sln /t:test\old_tests\test_old
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_nocoro
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_cpp20
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_cpp20_no_sourcelocation
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_fast
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_slow
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_module_lock_custom
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_module_lock_none
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\test_module_lock_none
+call msbuild /m /p:Configuration=%target_configuration%,Platform=%target_platform%,CppWinRTBuildVersion=%target_version% cppwinrt.sln /t:test\old_tests\test_old
 
 call run_tests.cmd %target_platform% %target_configuration%