feat(WP-0009): IHF GAAF Compliance Foundation — type registries, extension manifests, architectural contracts

Implements IHUB-WP-0009: closes four GAAF-2026 gaps before domain hub work begins.
- TypeRegistry helper + controllers/views (hub_kind, hub_capability_manifest)
- HubCapabilityManifest entity with validation and registry linkage
- ARCHITECTURE-LAYERS.md + CI-enforced boundary contracts
- Alembic migration 1743724800, fitness tests (Test/Architecture/)
- GAAF spec, Operational Architecture spec, domain hub extension guide
- Updates to CLAUDE.md, SCOPE.md, Schema.sql, Routes, FrontController, Types

state_hub_sync: pending (tunnel was STALE at completion time; run fix-consistency)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

contracts/functional/module-maturity-labels.md

@@ -0,0 +1,84 @@
+# Module Maturity Labels
+
+**Name:** module-maturity-labels
+**Version:** 1.0
+**Date:** 2026-03-31
+**Status:** Active
+**Layer:** Functional
+
+---
+
+## Purpose
+
+Defines the four maturity states used to label IHF functional modules and
+contract tables. These labels communicate to domain hub developers which
+surfaces are safe to depend on long-term.
+
+---
+
+## Labels
+
+### Stable
+
+The public interface **will not change** within the current major version.
+
+- Removing a field, renaming a table, or changing a column type is a **breaking
+  change** and requires a major version bump (e.g. IHF v1.0 → v2.0).
+- Adding a nullable or defaulted column is **not** breaking and may occur
+  without a version bump, but is documented in the changelog.
+- Suitable for all production use, including domain hub compilation dependencies.
+
+### Beta
+
+The interface is **finalised for typical use** but edge-case fields may change
+with a minor-version notice (e.g. IHF v0.2 → v0.3).
+
+- Core workflow fields are stable; metadata, computed, or supplementary fields
+  may be refined.
+- Suitable for production use with awareness: monitor the changelog before
+  upgrading.
+- A Beta module will be promoted to Stable once it has been used in at least
+  two deployed domain hubs without reported breaking-change issues.
+
+### Experimental
+
+The interface **may change without notice** between patch releases.
+
+- Use only for internal prototyping, spike implementations, or with explicit
+  opt-in acknowledgement.
+- Not suitable for domain hub production code.
+- A module remains Experimental until its design is confirmed by real usage.
+
+### Deprecated
+
+The module or field **will be removed** in the next major version.
+
+- A replacement is documented in the contract or in the schema comment.
+- The deprecated item remains functional until the major version boundary.
+- Domain hubs must migrate before upgrading to the next major version.
+
+---
+
+## Where Labels Are Used
+
+| Surface | How the label is expressed |
+|---|---|
+| Functional modules | `docs/functional-modules.md` maturity column |
+| `envelope_emission_contracts` table | `maturity` column (added in IHUB-WP-0009) |
+| `interaction_reporting_contracts` table | `maturity` column |
+| `widget_adapter_specs` table | `maturity` column |
+| Type registry entries | `status` column (`active` / `deprecated`) |
+| Contract files in `/contracts/` | `Maturity:` header field |
+
+---
+
+## Promotion Path
+
+```
+Experimental → Beta → Stable
+                 ↓
+            Deprecated → (removed at next major version)
+```
+
+Promotions are recorded in the module's entry in `docs/functional-modules.md`
+and the corresponding `maturity` column in the DB is updated.