feat(records): implement native eAkte vertical

docs/EAKTE_ARCHITECTURE.md

@@ -15,6 +15,28 @@ specialist procedure. It must not duplicate all document editing or storage.
 Implementation is tracked in
 [Records #1](https://git.add-ideas.de/GovOPlaN/govoplan-records/issues/1).
 
+## Implementation Status
+
+The native foundation is implemented through the work packages tracked by
+Records #2-#4:
+
+- versioned file plans and record classes;
+- stable records, immutable revisions, volumes, exact record items, and
+  chronology;
+- tenant isolation, optimistic concurrency, replay-safe writes, independent
+  valid/recorded time, purpose capture, institutional context, and search;
+- a full-height eAkte workspace with file plan, list, details, chronology,
+  temporal status, create/edit, and filing actions;
+- a provider-neutral Core filing contract with exact Files-version and
+  Cases-revision providers.
+
+The remaining delivery order is intentionally visible rather than implied:
+Records #5 owns closure, retention, holds, appraisal, and disposition; #6 owns
+recovery and signed evidence; #7 requires selection and target testing of an
+archive/xdomea provider; and #8 proves the reference journey. Restricted
+per-record access grants also remain a dedicated access-policy slice. No
+archive or destructive effect is currently claimed.
+
 ## Ownership Boundary
 
 Records owns: