Clarify remaining native DLP acceptance and Windows build prerequisites

docs/native-runtime/README.md

@@ -241,6 +241,19 @@ both official upstream references remain unchanged. The single-commit mailbox
 checkpoint remains **uncompiled and runtime-unverified**. The shipped project
 runtime is unchanged; source assertions cannot substitute for the native gates.
 
+### Rejected package: dependency scope
+
+The pinned Chromium `DEPS` requires the rejected x86 package under `checkout_win`,
+independently of the build target CPU. Its source consumers are updater test
+fixtures: `chrome/updater/BUILD.gn` selects `UpdaterSetup_test.exe` as test data,
+and `third_party/updater/BUILD.gn` defines the test-only `old_updater` copy target.
+Branded updater tests may include x86 fixtures even in an x64 build. No direct
+updater dependency was found in Electron's app/link target declarations; the
+transitive GN graph has not been generated or verified. Therefore this package
+is not identified as a compiler tool, but the official full sync remains failed.
+This read-only analysis authorizes neither skipping dependencies nor changing
+antivirus policy. ATL/MFC remains independently missing at the host check.
+
 ### Patch readiness before compilation
 
 ATL/MFC is required for the native toolchain, not for the Python patch import