Isolate manual artifact validation without package publication

DAILY-RELEASE.md

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+# Daily releases (not enabled)
+
+This branch currently runs manual artifact validation only. The independent
+three-branch dispatcher is on main and has no schedule yet. NuGet.org and
+GitHub Release publication are disabled for the initial runs.
+
+See [ACTION-TESTING.md](ACTION-TESTING.md) for artifact names, the macOS native
+package used by graphics smoke tests, and the steps required before daily
+builds are enabled.