Document centralized LLM asset ownership

docs/policy/architecture.md

@@ -44,6 +44,13 @@ must not compose the application or take ownership of process behavior. The
 current packages implementing these layers are inventoried in
 [Internal Overview](../internal/overview.md).
 
+The root `assets` package is a content-only dependency leaf. It may expose a
+read-only embedded filesystem, but it must contain no business logic and must
+not depend on `internal` packages or PromptKit. Consumers scope that filesystem
+to the content they own; the root package is not a behavioral registry or a
+public extension contract. The rationale and compatibility consequence are
+recorded in [ADR-0011](../adr/0011-centralize-llm-assets.md).
+
 The following dependency boundaries are mandatory:
 
 - extractors and validators do not depend on concrete input adapters;
@@ -73,6 +80,12 @@ Extract modules own artifact semantics, prompt use, response schemas, and
 domain interpretation. Domain-specific concepts remain in the relevant module,
 validator, shared domain helper, and artifact contract.
 
+Physical centralization of LLM-facing content does not transfer semantic
+ownership from those modules. Modules retain their manifests, response-schema
+identities, prompt ordering, and registration, while reading only their scoped
+content subtree. Generic framework code remains domain-neutral when it reads
+its own scoped generic assets from the shared content container.
+
 Typed artifact registrations declare one stable artifact kind and exact Go
 type from extraction through merge, normalization, and semantic validation.
 Pipeline resolution requires a compatible codec and matching kind-specific