docs(readme): refresh status and link the phase plans

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QeqhJpYQyghASjiJo5EhGg

README.md

@@ -3,7 +3,8 @@
 Shared ingestion library for OKF (Open Knowledge Format) bundles.
 
 Status: pre-implementation. This repository currently contains the project
-scaffold and scope definition only; no pipeline code has been written yet.
+scaffold, the scope definition, and detailed plans for each phase (under
+`docs/plan/`); no pipeline code has been written yet.
 
 ## Planned scope (v1)
 
@@ -43,18 +44,23 @@ No security functionality is reimplemented here.
 ## Roadmap
 
 The library is built in four phases so that every known OKF surface in the
-ecosystem is eventually covered:
+ecosystem is eventually covered. Each phase has a detailed plan with
+verification criteria:
 
-1. Spec-based ingestion (Python) with byte-exact golden fixtures.
-2. Bundle inbox and external-bundle import (Python), guard-gated.
+1. Spec-based ingestion (Python) with byte-exact golden fixtures —
+   [plan](docs/plan/phase-1-door-a.md).
+2. Bundle inbox and external-bundle import (Python), guard-gated —
+   [plan](docs/plan/phase-2-doors-b-c.md).
 3. Configurable bundle contract (types, layers, frontmatter sets, and
    reserved-file policy as configuration), enabling stricter bundle
-   profiles such as `strict-v1`.
+   profiles such as `strict-v1` —
+   [plan](docs/plan/phase-3-configurable-contract.md).
 4. A `node/` half: a zero-dependency Node/ESM package (importable and
    CLI-invokable, vendored per consumer) providing bundle checking, index
    generation, inbox processing, and document conversion for the OKF
    second-brain plugin ecosystem. The Python and Node halves share the OKF
-   contract and fixture suite, not code.
+   contract and fixture suite, not code —
+   [plan](docs/plan/phase-4-node-half.md).
 
 ## Non-goals