feat: implement governed service directory

README.md

@@ -3,3 +3,30 @@
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 **Repository type:** module (domain).
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+
+Portal owns service discovery, presentation, and channel entry. Its
+`portal.service_directory` capability projects provider-owned, versioned
+service definitions into available, explainably unavailable, or undiscoverable
+entries. It does not persist the institutional service promise or import Cases,
+Forms, Workflow, Access, or Policy tables.
+
+The capability works in a reduced composition without a Services provider by
+returning an empty directory. When a provider is present, provider-level access
+filtering remains authoritative and Portal adds only presentation-oriented
+availability checks for publication, effective time, audience, module, and
+capability requirements.
+
+The tenant-scoped `/api/v1/portal/services` endpoint and `/portal` WebUI expose
+the projection. Audience visibility is derived from trusted principal and
+active function-assignment state on the server.
+
+`POST /api/v1/portal/services/{service_id}/launch` re-fetches and re-evaluates
+the exact Service revision before any effect. URL entries return a validated
+redirect. Case, form, and workflow bindings delegate through the optional
+`cases.service_launcher`, `forms_runtime.service_launcher`, and
+`workflow_engine.service_launcher` contracts; each is tenant-bound and
+replay-safe. A missing owner launcher makes the entry explainably unavailable.
+Form launch resolves an exact published `<form-id>/<revision>` and returns the
+owner's Form-instance route rather than persisting values in Portal.
+
+See [docs/SERVICE_DIRECTORY_CONCEPT.md](docs/SERVICE_DIRECTORY_CONCEPT.md).