feat: add typed tier assurance guardrails

tenancy.yaml

@@ -0,0 +1,36 @@
+# Canonical declaration: NetKingdom Tenancy Posture v0.1 draft-8.
+schema_version: "0.1"
+framework: netkingdom-tenancy-posture
+service: coulomb-observatory
+role: design-time-pricing-analysis
+
+tenancy:
+  current: { I: 0, A: 0, E: 0, P: "n/a", R: "n/a", V: 0 }
+  target:  { I: 0, A: 0, E: 0, P: "n/a", R: "n/a", V: 0 }
+  reviewed: "2026-08-17"
+  review_due: "2027-02-17"
+  service_class: interactive
+  permanent: [I, A, E, P, R, V]
+  reason:
+    I: >-
+      The observatory's local HTTP surface is unauthenticated and single-user
+      by design. It is not a production tenant service.
+    A: >-
+      No authorization boundary exists because the local surface is not
+      exposed or supported as a shared service.
+    E: >-
+      No runtime tenant boundary exists. Project JSON is local proving-ground
+      data and must not be mistaken for a multi-tenant datastore.
+    P: >-
+      No runtime datastore exists; repository JSON is source material, not a
+      provisioned substrate.
+    R: >-
+      No runtime data is retained. Repository history follows source-control
+      governance rather than a service erasure policy.
+    V: >-
+      No availability position exists for a local design-time tool.
+  gap:
+    I: >-
+      Permanent only while the server remains local and single-user. Any
+      proposal to expose it creates a new service and requires reassessment
+      before deployment.