docs(v4.0.0): step 6a withdrawn -- drives that come and go are built as v3 has them

Captain Bob, 2026-10-07.  Rulings 6 and 8 of MESH.md 8.1 (a device
identity in the block header, a returning device's old numbers, release
by moving its blocks off, holes) were given without v3's design having
been shown.  MESH.md 8.7 sets v3's design beside them: a removable drive
is a person's, known by its signature; WIREBIND; it joins at the tail and
only the tail leaves; EJECT flushes to the drive and kills the user's VM.

ENGINE.md steps 7 and 8 now say that is where it is built.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/v4.0.0/ENGINE.md

@@ -409,7 +409,14 @@ its logs.
 6. **Hera as v3 has her.** `init.4th` runs on the node; v3's whole POST
    passes; v3's parity lines.
 7. **The fleet.** Hestia and Artemis; message delivery; who runs next.
+   With Artemis: she is the owner of the disk, who says it may be
+   formatted, so that the disk is written as well as read (`MESH.md` step
+   6); and a drive that arrives is registered by her, at the chain's tail.
 8. **Identity and the prompt.** Zuse; `[zuse@Hera] ok>`.
+   With identity: drives that come and go, as v3 has them — the
+   home-blocks signature, `WIREBIND`, the user's VM born from the drive,
+   `EJECT`, and a surprise pull (`MESH.md` 8.7, which says why the storage
+   step that was to build them another way was withdrawn).
 
 Moving words from the assembled nucleus to `forth79.4th` goes on beside
 these, a group at a time, with POST after each.