Remove registry-only README sections

Author: AnastaZIuk

README.md

@@ -200,57 +200,3 @@ Multiple backends can coexist with ordered fallback. If we later replace `GitHub
 Release publishing policy in this prototype is intentionally simple:
 - standalone assets are published as individual files
 - bundles are published as zip archives
-
-## First-party registry layout
-
-<details>
-<summary>Click to expand</summary>
-
-```text
-media/
-  assets/
-    mesh/
-      standalone/
-        obj/
-        ply/
-        stl/
-      bundles/
-        obj/
-    image/
-      standalone/
-        exr/
-        png/
-        jpg/
-        jpeg/
-        tga/
-        dds/
-        ktx/
-    photometry/
-      ies/
-    scene/
-      mitsuba/
-        xml/
-        serialized/
-        bundles/
-    archive/
-      zip/
-    data/
-      text/
-      json/
-
-references/
-  perf/
-    meshloaders/
-
-licenses/
-```
-
-</details>
-
-## Current scope
-
-This is only the starting point.
-
-The official first-party Nabla registry is intentionally designed so that the
-rest of the current Nabla `media` tree can be migrated there later under the
-same model.