revisão e complementação da documentação do projeto

docs/adr/ADR-009-risk-tiers-for-capabilities.en-us.md

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+# ADR-009: Risk tiers R0-R4 for capabilities
+
+**Status:** Accepted.
+**Source:** this ADR is the canonical record of this decision. For implementation and validation context, see `RI/docs/AS-BUILT.md` and, where applicable, the relevant contract in `RI/docs/interfaces/`.
+
+## Context
+
+How to classify capabilities.
+
+## Decision
+
+Risk tiers R0–R4 in the Registry, controlling required approval/observability.
+
+## Alternatives Considered
+
+No formal classification.
+
+## Consequences
+
+EP-02-T01 includes mandatory `risk_tier` in the manifest schema.