Implement SAND-WP-0003: validation meta-framework extraction

Port e2e-framework schema, runner, and reporter into wise-validator with
sand-boxer CLI integration, validate run CLI, unit tests, registry capability,
and operator docs.

registry/capabilities/validation.compose-e2e.md

@@ -0,0 +1,42 @@
+---
+id: capability.validation.compose-e2e
+name: Compose E2E Validation
+summary: Cross-repo use-case validation — health polling, test execution, and State Hub result reporting on sand-boxer-established compose environments.
+owner: wise-validator
+status: draft
+domain: infotech
+tags: [validation, e2e, health, compose, cross-repo, use-case]
+
+maturity:
+  discovery:
+    current: D4
+    target: D6
+    confidence: high
+    rationale: >
+      Charter (INTENT.md) and sand-boxer integration contract define scope.
+      Extraction from the-custodian/e2e-framework completes the validation half.
+  availability:
+    current: A2
+    target: A5
+    confidence: medium
+    rationale: >
+      validate run CLI v0 and sand-boxer profile.compose-e2e integration land
+      in SAND-WP-0003. the-custodian shim deferred to SAND-WP-0004.
+
+external_evidence:
+  completeness:
+    level: C2
+    name: Partial
+    confidence: medium
+    basis: scope_vs_intent_and_consumer_expectations
+    satisfied_expectations:
+      - e2e.yml v1 contract parsing
+      - health-wait and test_command on ready sandbox
+      - State Hub e2e_result events
+      - sand-boxer create/destroy without embedded provision
+    broken_expectations:
+      - the-custodian make e2e shim not yet migrated
+      - activity-core scheduled validation not wired
+    out_of_scope_expectations:
+      - sandbox provision (sand-boxer)
+      - agent harness (glas-harness)

registry/indexes/capabilities.yaml

@@ -1,4 +1,6 @@
 version: 1
-updated: '2026-06-16'
-domain: helix_forge
-capabilities: []
+updated: '2026-06-23'
+domain: infotech
+capabilities:
+  - id: capability.validation.compose-e2e
+    path: registry/capabilities/validation.compose-e2e.md