Initial public ModelForge release

docs/architecture/SHADOW_AND_DUAL_READ.md

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+# Shadow and dual read
+
+Shadow targets are separate storage identities and are exposed only to evaluation/admin or an
+explicit project shadow route. Ordinary production consumers continue using the current binding.
+Compatible adapters may execute one request against current and shadow, but persist only result IDs,
+metrics, latency, errors and evidence references—not content.
+
+Shadow completion records a `MigrationShadowSession`. Success reaches `READY_FOR_CUTOVER`; it never
+switches traffic. An isolated technical verdict and project-promotion verdict remain distinct.