ADR 0131: everything on the mesh speaks to the broker seat, and AMQP is not a provision

Taken during the outage of 2026-09-27, when the protocol leaked into the seat's
contract: to hold mesh-broker a module had to provide amqp, so the module that
will carry the bus could not hold the seat that names the bus, while the module
being retired could. Supersedes 0127. Modules depend on the seat and reach the
bus through the sdk; no manifest provides or requires amqp; the old broker's
module and the two modules that required it leave the catalogue; the AMQP
transport is deleted once every node reports on the new bus.

Design 28 step 5 rewritten under it: the seat handover becomes its own task and
is built first, because the seat the control plane dereferences cannot be empty
in between — that emptiness was the outage. The cost note now carries what was
measured rather than what was assumed.

0128 and 0130 extended 0127; each now rests on 0131 with a dated note and
changes nothing it decided. Every other citation of 0127 names its replacement.
records.py still fails on 0120/0112, which predates this branch.

02-DECISIONS/0128-the-mesh-bus-is-required-not-ambient.md

@@ -4,11 +4,18 @@ status: accepted
 date: 2026-09-26
 deciders: jochen
 reconstructed: false
-extends: 02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md
+extends: 02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
 ---
 
 # 128. The mesh bus is required, not ambient
 
+
+> **Pointer repointed, 2026-09-27.** This record was written extending
+> [ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)), which
+> [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md) has since superseded — AMQP is
+> not a provision at all. Nothing decided here changes; the frontmatter now rests on the live record,
+> and the citations below are read with that in mind.
+
 ## Context
 
 [Design 29](../03-DESIGN/01-to-be/32-what-a-module-declares.md) opened by saying the bus is
@@ -72,7 +79,7 @@ process in the path and nothing waiting on a bus account to create bus accounts.
 whose provider is the mesh itself.
 
 **A module may also provide a NATS server of its own, and that is a different interface.** Exactly
-as the AMQP broker provides `amqp` ([ADR 0127](0127-amqp-is-a-provision-not-the-bus.md)), a module
+as the AMQP broker provides `amqp` ([ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md))), a module
 may run its own NATS and offer it as a backing service. That interface is **`nats`**; the mesh's
 own bus is **`mesh-bus`**; the two are never the same name, because a manifest that said `nats`
 could mean either and the difference is the whole architecture. The rule from 0119 decides which
@@ -109,7 +116,7 @@ is legitimate: a private bus is a backing service, never a channel to another mo
 
 - [ADR 0125](0125-the-bus-is-the-only-broker.md) — superseded by 0119; its bootstrap argument is
   narrowed here to the case it supports.
-- [ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) — a broker as a backing service; this
+- [ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)) — a broker as a backing service; this
   applies the same shape to the mesh's own bus and separates the two names.
 - [ADR 0043](0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md) — authority from
   declarations, which this leaves untouched.