Publish ITWorx Pulse source

docs/architecture/adr/0008-stale-is-unknown.md

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+# ADR 0008 — Stale or missing required telemetry is Unknown
+
+**Status:** Accepted baseline
+
+## Decision
+
+When required telemetry is unavailable beyond its freshness policy, Pulse reports Unknown rather than retaining or inferring Healthy.
+
+## Rationale
+
+False green status is more dangerous than explicit uncertainty.
+
+## Consequences
+
+- Responses carry freshness metadata.
+- Alert rules define unknown behavior.
+- UI shows last known value only with age.
+- Tests inject stale/missing sources throughout the product.