feat: freeze repository navigation contract

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a0230c-b06c-7641-808a-e191b6d1da49

README.md

@@ -42,6 +42,12 @@ from hub_core.contracts import CONTRACT_VERSION, extension_contract_root
 contract_root = extension_contract_root()
 ```
 
+The wheel also includes the frozen `helixforge.repository-navigation` 1.0.0
+receiving and query contract. Its packaged schemas, fixtures, compatibility
+matrix, and read-only OpenAPI surface are located with
+`repository_navigation_contract_root()`; normative rebuild and cursor rules
+are in `docs/repository-navigation-contract.md`.
+
 ## Runtime scaffold
 
 Install the runtime extra and start the API, MCP, or migration process through
@@ -105,6 +111,8 @@ are tracked in `HUB-WP-0006`.
   repo, DoI, TPSC/GDPR, risk/alert, and progress tools.
 - Packaged `helixforge.hub-extension` 0.1.0 Tier 1 schemas, OpenAPI port
   fragments, event catalog, compatibility matrix, and ops-hub fixture.
+- Packaged `helixforge.repository-navigation` 1.0.0 schemas, fixtures,
+  compatibility policy, and read-only projection query contract.
 - Injectable primary runtime scaffold with five named ports, health/readiness,
   API/MCP/migration commands, and a locked non-root OCI image.