Modules declare their own seats; the mesh reserves mesh-*

The architecture 0117 opened needs a module to offer a service as a role on
the bus — one holder, addressed by what it does. A closed table in the
controller cannot express that: a capability a module contributes would
require changing the mesh itself.

But 0110 closed the set for a good reason — nothing could say what seats a
mesh had, and the hand count came out at eleven of thirteen. That argues for
enumerable, not hardcoded, and 0110 weighed free-form against a fixed table
without considering a third option: closed at any moment and derived from
the catalogue. A derived list cannot drift, which is how the count broke.

So: the mesh's seats stay the mesh's, reserved by the mesh- prefix so the
prefix is the rule and there is no list to maintain; ten seats are renamed
to restore 0079's convention; everything 0110 decided about what a seat IS
survives untouched.

Design 29 carries the declaration model: three namespaces, subjects derived
from local names so a manifest survives the wire changing, queues never
declared, five relationships (the job and state shapes 0041 had no room
for), and the build-publish-deploy lifecycle with hard, soft and build-time
dependencies distinguished.

0041 gets a progressive insight: "no per-consumer setup, only a
subscription" was a fact about a topic exchange, and a JetStream durable
consumer is a real object someone creates.

WBS 1.3/1.4 were wrong and say so: streams come at registration and
consumers at assignment, so only the foundation set belongs at genesis.
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| [`23-choosing-a-provider.md`](23-choosing-a-provider.md) | Which of several providers of a kind serves a consumer, and when a module carries its own instead | [ADR 0084](../../02-DECISIONS/0084-which-provider-serves-a-consumer.md), [ADR 0027](../../02-DECISIONS/0027-a-provision-names-what-the-consumer-is-coupled-to.md) |
| [`24-the-secrets-vault.md`](24-the-secrets-vault.md) | The module that owns a secret — a `secret` provision, and the boundary of what it owns | [ADR 0085](../../02-DECISIONS/0085-a-secret-is-a-provision.md), [ADR 0031](../../02-DECISIONS/0031-the-control-plane-authenticates-nobody.md), [ADR 0048](../../02-DECISIONS/0048-a-provider-creates-the-credential-the-mesh-minted.md) |
| [`25-the-bus-on-nats.md`](25-the-bus-on-nats.md) | **Proposed.** The architecture of the mesh's bus on NATS: what rides which subject under which guarantee and whose account, how a node joins, how a person reaches a tool, and how the mesh moves from the bus it has | [ADR 0106](../../02-DECISIONS/0106-the-bus-is-nats.md), [ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md), [ADR 0043](../../02-DECISIONS/0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md), [ADR 0083](../../02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md) |
| [`26-the-seats.md`](26-the-seats.md) | **Proposed.** What a mesh can have one of, who fills each, and a seat's holder answering for the provision it delivers — including the `git` seat a build's source can live on | [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md), [ADR 0111](../../02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md), [ADR 0109](../../02-DECISIONS/0109-a-package-registry-seat-is-one-per-ecosystem.md) |
| [`27-a-module-requires-the-mesh-resolves.md`](27-a-module-requires-the-mesh-resolves.md) | **Proposed.** One concept for everything a module needs: a requirement with a contract, answered by one of four kinds of provider, resolved at assignment or refused. Retires settings, placeholders, facts and paths in definitions | [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md), [ADR 0113](../../02-DECISIONS/0113-the-vault-makes-every-secret.md), [ADR 0114](../../02-DECISIONS/0114-a-shared-credential-rotates-over-two-credentials.md), [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md) |
| [`26-the-seats.md`](26-the-seats.md) | **Proposed.** What a mesh can have one of, who fills each, and a seat's holder answering for the provision it delivers — including the `git` seat a build's source can live on | [ADR 0118](../../02-DECISIONS/0118-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)), [ADR 0111](../../02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md), [ADR 0109](../../02-DECISIONS/0109-a-package-registry-seat-is-one-per-ecosystem.md) |
| [`27-a-module-requires-the-mesh-resolves.md`](27-a-module-requires-the-mesh-resolves.md) | **Proposed.** One concept for everything a module needs: a requirement with a contract, answered by one of four kinds of provider, resolved at assignment or refused. Retires settings, placeholders, facts and paths in definitions | [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md), [ADR 0113](../../02-DECISIONS/0113-the-vault-makes-every-secret.md), [ADR 0114](../../02-DECISIONS/0114-a-shared-credential-rotates-over-two-credentials.md), [ADR 0118](../../02-DECISIONS/0118-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)) |
| [`28-building-the-bus.md`](28-building-the-bus.md) | **Proposed.** The five steps of the bus work in the order their dependencies allow, each ending at a bed — with the surface measured, so no step's size is a guess | [ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md), [ADR 0106](../../02-DECISIONS/0106-the-bus-is-nats.md), [ADR 0074](../../02-DECISIONS/0074-the-wire-is-specified-not-the-types.md) |
| [`29-what-a-module-declares.md`](29-what-a-module-declares.md) | **Proposed.** What a module declares and what the bus derives from it: three namespaces, subjects from local names, queues never declared, the five relationships, and the build-publish-deploy lifecycle on one bus | [ADR 0118](../../02-DECISIONS/0118-a-module-declares-its-own-seats.md), [ADR 0117](../../02-DECISIONS/0117-the-bus-is-the-only-broker.md), [ADR 0041](../../02-DECISIONS/0041-events-are-a-relationship.md) |
## Not yet written
- **The remaining six contexts.**