Adopt the shared interface pattern language

docs/INTERFACE_PATTERN_MIGRATION.md

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+# Portal Interface Pattern Migration
+
+Portal is a public-service-style directory for authenticated institutional
+users. Services owns definitions, Policy/provider capabilities own availability,
+and Cases, Forms Runtime, or Workflow Engine owns the launch effect. Portal
+does not import those modules or infer their state.
+
+| Surface | Task and archetype | Consequence and state contract |
+| --- | --- | --- |
+| `/portal` toolbar | Find and filter services | Search and the unavailable-service toggle affect only the directory result. Counts are announced as the result changes. |
+| Service directory | Public service/entry catalogue | Loading, empty, failed, available, unavailable, and capability-unknown states remain distinct. Only discoverable service metadata is rendered. |
+| Availability blocker | Explained disabled action | Open remains in its stable action position. The blocker states why launch is unavailable, what must happen, the responsible actor, and the destination. |
+| Open service | Consequential handoff | Portal re-evaluates the exact service revision with a replay-safe request, then hands off to the provider-owned route. It never reports success without a destination. |
+
+The directory uses Core buttons, toggle, status, loading, alerts, scrolling,
+blocker explanation, guarded navigation, and documentation help. Availability
+is expressed in text as well as color. The responsive toolbar stacks before the
+service list and every action remains keyboard-operable. Optional owner modules
+remain capability-based and an unavailable provider does not become a broken
+link.
+
+Verification:
+
+- `npm run test:interface-pattern`
+- Portal service-directory and manifest tests
+- the Core TypeScript graph, structural localization audit, theme check, module
+  permutations, and full-product bundle budget