Retire capability: Haskell/IHP build-chain problems, superseded by core-hub

Maturity reassessment (2026-07-07): discovery D3->D5 to honestly reflect
Phases 0-9 being complete (real controllers, tests, versioned /api/v2 with
OpenAPI/OAuth/SDKs/webhooks) -- the initial D3 undersold real depth.

Status set to deprecated. Availability deliberately held at A1: the
Haskell/IHP build chain is the specific reason for retirement, not raised
despite the deep feature implementation. Completeness raised to C3 (nine
phases delivered); the one broken expectation is build-chain reliability
itself. Reliability held at R0 -- retirement is negative evidence, not a
promotion.

relations.related_to now points at capability.infotech.core-hub, the
contract-first Python/FastAPI/Postgres rebuild (see core-hub/SCOPE.md),
which plans Inter-Hub /api/v2 compatibility and a migration path.

Requested by Bernd as a follow-up to the reuse-surface REUSE-WP-0017
coverage sweep.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

registry/indexes/capabilities.yaml

@@ -1,15 +1,15 @@
 version: 1
-updated: '2026-07-06'
+updated: '2026-07-07'
 domain: helix_forge
 capabilities:
 - id: capability.infotech.interaction-hub-framework
   name: Interaction Hub Framework (IHF)
   summary: Specification and reference implementation of a governed, observable interaction substrate
     connecting rendered UI widgets to structured feedback, requirements, decisions, implementation changes,
-    and observed outcomes.
-  vector: D3 / A1 / C1 / R0
+    and observed outcomes. Retired (Haskell/IHP build-chain problems); superseded by core-hub.
+  vector: D5 / A1 / C3 / R0
   domain: infotech
-  status: draft
+  status: deprecated
   owner: inter-hub
   path: registry/capabilities/capability.infotech.interaction-hub-framework.md
   tags:
@@ -17,5 +17,6 @@ capabilities:
   - governance
   - ihp
   - haskell
+  - retired
   consumption_modes:
   - application