docs(#3034): sweep the remaining stale rebuild-shape references

argus caught `approvals.md` still describing the old serial chain under the old
node name. Grepping the name across *all* tracked files rather than just `*.rs`
turned up three more, all in `coordinator.md`: the node-inventory rows for `Swap`
and the bookkeeping tail, and the rebuild shape diagram.

Three of the four were in the file I had edited in the previous commit to add the
brace section, which is the point worth recording: I grepped the *concept* I had
changed (`lease`) and the *symbol* I had renamed, but scoped the rename grep to
Rust. Neither pass could see an old node name sitting in prose.

Also adds the missing `AgentWindow` row to the node inventory.

docs/approvals.md

@@ -319,8 +319,9 @@ running and a restart resumes at node granularity:
    `applied/<n>/main` (which the deploy already fast-forwarded to
    the reviewed PR head).
 2. The rebuild subgraph `DeployApply` grows into the DAG builds and
-   swaps the container (`Prebuild → StopForUpdate → Swap → PostSwap`,
-   plus `Reconcile`). Nix evaluates against the staged lock.
+   swaps the container (`AgentWindow` bracing `Prebuild → StopForUpdate
+   → Swap → RebuildBookkeeping`, plus `Reconcile`). Nix evaluates
+   against the staged lock.
 3. On success — `FinalizeDeploy` drops the rollback ref, plants
    `deployed/<id>`, then `meta::finalize_deploy(name, sha, "deployed/
    <id>")` stages `flake.lock` and commits with