Address PR feedback: remove ProjectInspector.csproj files, use 'placeholder' instead of 'dummy', keep INCLUDE_* variables

Co-authored-by: rolfbjarne <249268+rolfbjarne@users.noreply.github.com>

Author: Copilot

Make.config

@@ -232,7 +232,7 @@ endif
 export DEVELOPER_DIR=$(XCODE_DEVELOPER_ROOT)
 export MD_APPLE_SDK_ROOT=$(abspath $(XCODE_DEVELOPER_ROOT)/../..)
 else
-# On Linux, set dummy Xcode values
+# On Linux, set placeholder Xcode values
 XCODE_VERSION=26.2
 XCODE_URL=
 XCODE_PRODUCT_BUILD_VERSION=
@@ -303,16 +303,6 @@ INCLUDE_DEVICE=1
 -include $(TOP)/Make.config.local
 -include $(TOP)/configure.inc
 
-# On Linux, override platform includes to skip native code
-ifdef IS_LINUX
-INCLUDE_IOS=
-INCLUDE_MAC=
-INCLUDE_TVOS=
-INCLUDE_MACCATALYST=
-INCLUDE_SIMULATOR=
-INCLUDE_DEVICE=
-endif
-
 # misc Xcode tool
 CLANG=$(CCACHE)$(XCODE_DEVELOPER_ROOT)/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
 SWIFTC=$(XCODE_DEVELOPER_ROOT)/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc