Register shard-wiki capabilities (7 wiki.* registry entries)

Adds capability.wiki.{shard-orchestration, adapter-contract, page-model,
coordination-journal, overlay, federation-models, engine-typed-extensions}
with honest D/A/C/R maturity vectors, relations, and shard-wiki spec/test
evidence; updates registry/indexes/capabilities.yaml. reuse-surface validate: ok.
Source: shard-wiki SHARD-WP-0013 T1.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

registry/capabilities/capability.wiki.adapter-contract.md

@@ -0,0 +1,103 @@
+---
+id: capability.wiki.adapter-contract
+name: Capability-Aware Shard Adapter Contract
+summary: A versioned backend interface where each binding declares a verified capability profile (positions on capability spectra), so federation ops degrade by capability.
+owner: shard-wiki
+status: draft
+domain: helix_forge
+tags: [wiki, adapter, capability, contract, conformance, shard-wiki]
+
+maturity:
+  discovery:
+    current: D5
+    target: D6
+    confidence: high
+    rationale: >
+      Fifteen capability spectra with an orthogonal core + implication rules, plus
+      a normative contract spec (TSD Section A); derived from a ~23-system synthesis.
+  availability:
+    current: A2
+    target: A5
+    confidence: medium
+    rationale: >
+      AdapterContract + a read/write FolderAdapter + a conformance suite that
+      verifies declared profile == observed behaviour exist as a source module.
+
+external_evidence:
+  completeness:
+    level: C2
+    name: Partial
+    confidence: medium
+    basis: scope_vs_intent_and_consumer_expectations
+    satisfied_expectations:
+      - versioned interface with declared, conformance-verified capability profiles
+      - one concrete adapter (file-store) passes the conformance suite
+    broken_expectations:
+      - only one substrate implemented (git-IS-store, REST, CRDT adapters planned)
+    out_of_scope_expectations:
+      - hosting backends
+  reliability:
+    level: R1
+    confidence: low
+    basis: consumer_quality_signals
+    known_reliability_risks:
+      - single adapter implemented so far
+
+discovery:
+  intent: >
+    Mediate heterogeneity at one narrow waist: a backend participates by implementing a
+    versioned interface and declaring a verified position on each capability spectrum.
+  includes:
+    - capability profile as data (orthogonal-core spectra + implied positions)
+    - operation verbs (read/write/diff/merge/notify/.../derive-projection/execute)
+    - a conformance suite (profiles verified, not self-asserted)
+  excludes:
+    - assuming uniform backend capabilities
+  use_cases:
+    - "shard-wiki UseCaseCatalog UC-34..UC-43, UC-50, UC-57, UC-60..UC-69 (shard attachment & adapter binding)"
+
+availability:
+  current_level: A2
+  target_level: A5
+  current_artifacts:
+    - "shard-wiki/src/shard_wiki/adapters/"
+  consumption_modes:
+    - source module
+
+relations:
+  depends_on:
+    - capability.wiki.page-model
+  supports:
+    - capability.wiki.shard-orchestration
+
+evidence:
+  documentation:
+    - "shard-wiki/spec/TechnicalSpecificationDocument.md (Section A)"
+    - "shard-wiki/spec/CoreArchitectureBlueprint.md (Section 6)"
+  tests:
+    - "shard-wiki/tests/test_folder_adapter.py"
+    - "shard-wiki/tests/test_conformance.py"
+
+consumer_guidance:
+  recommended_for:
+    - exposing any page store as a capability-described, conformance-checked shard
+  not_recommended_for:
+    - backends that cannot honestly describe their capabilities
+  known_limitations:
+    - reference implementation covers the file-store substrate only so far
+---
+
+# Capability-Aware Shard Adapter Contract
+
+The bottom narrow waist of shard-wiki: a versioned interface plus a **verified** capability
+profile per binding. Core logic is written once against capabilities (not per-backend), and
+the conformance suite rejects profiles whose declared abilities don't match observed behaviour.
+
+## Assessment notes
+
+### Discovery
+Fifteen spectra reduced to an orthogonal core with implication rules (CoreArchitectureBlueprint
+Section 6.5); normative in TSD Section A.
+
+### Availability
+`adapters/` ships the contract, a folder adapter, and `assert_conformant`.