feat(registry): add Integration Definition schema v0.1

Define the open-reuse integration asset registry format with JSON Schema,
authoring template, discovery index, and analyze→classify→refactor→maintain
lifecycle documentation. Validates against the markitect-quarkdown reference
integration.

Closes OPEN-WP-0002.

templates/integration-entry.template.yaml

@@ -0,0 +1,87 @@
+# Copy to <consuming-repo>/integration/<id>.integration.yaml
+# Register the entry in open-reuse registry/indexes/integrations.yaml after review.
+schema_version: open-reuse.integration.v0.1
+id: example-integration
+name: Example Integration
+description: >
+  One paragraph describing the proven integration, its value, and the local
+  system it connects to upstream open-source software.
+status: draft
+owner: team-or-repo-slug
+
+local:
+  repo: example-repo
+  path: integration/example.integration.yaml
+  system: Example Product
+
+upstream:
+  name: Upstream Project
+  project_url: https://github.com/org/upstream
+  homepage: https://upstream.example/
+  version_policy: ">=1.0.0 <2.0.0"
+  current_version: "1.4.2"
+  monitor:
+    releases: true
+    tags: true
+    security_advisories: true
+    license_changes: true
+
+reuse:
+  primary_reuse_mode: adapter
+  secondary_reuse_modes:
+    - dependency-reuse
+  risk_level: medium
+  rationale: >
+    Upstream behavior is wrapped behind a local adapter interface; upstream
+    API changes require validation but do not directly touch local systems.
+
+boundary:
+  type: adapter
+  local_adapter: example.adapter.ExampleAdapter
+  local_interface: example.contracts.UpstreamPort
+  reused_surface: upstream public API / CLI
+  entry_point: example.adapters
+  contracts:
+    - example.integration.v1
+  fragility_points:
+    - CLI flag changes
+    - output format changes
+
+runtime:
+  required:
+    - Upstream CLI 1.x
+    - Python 3.11+
+
+validation:
+  harness: python3 -m pytest tests/integration/
+  skip_without_runtime: true
+  checks:
+    - contract compatibility
+    - golden-path smoke test
+    - failure-mode diagnostics
+  policy: required-before-update
+
+update_policy:
+  default_action: require-maintainer-review
+  auto_eligible: false
+
+risks:
+  sensitivity:
+    - breaking API changes
+    - license changes
+    - security advisories
+  escalation_triggers:
+    - validation failure
+    - upstream major release
+
+maintenance:
+  maintainers:
+    - team-platform
+  escalation_conditions:
+    - upstream release detected
+    - validation failure
+    - dependency requirement change
+
+audit:
+  registered_at: "2026-06-24"
+  registered_by: integration-maintainer