Publish reciprocal canon federation interface

Assistant: codex
Assistant-Model: gpt-6-astra
Assistant-Session: 01a070b5-4994-7271-bd8b-7c3dbcedec4b

canon.yaml

@@ -1,7 +1,7 @@
 repository: info-tech-canon
 title: InfoTechCanon
 status: service-baseline
-version: 0.11.1
+version: 0.12.0
 description: >
   An evolving, markdown-first canon for building interoperable, adaptable,
   and extensible information-processing systems.
@@ -222,3 +222,9 @@ next_actions:
   - keep ITC-CAP 0.4.0 frozen; do not change its shape without a new minor
   - collect two independent EmissionCadenceDeclaration source implementations
     before promoting ITC-EMISSION-CADENCE beyond draft
+
+interface_cards:
+  - id: info-tech-canon/federation-interface
+    path: infospace/interfaces/federation.yaml
+    status: published
+    version: 0.1.0