Review: three ADRs no longer said what we had concluded

A sweep for claims overtaken by the last few days. Annotated rather than
rewritten, following the pattern already in 0049 -- what changed and why is the
useful part, and an accepted record should not quietly become something else.

0057's init section was wrong on all three of its claims. It said the host
needs FOUR things from an init; 0061 reduced that to one. It said every machine
the mesh targets already has systemd; Alpine does not, and it is the intended
first node. It said there is no second init to abstract over; there is now, and
the answer is still not an abstraction -- it is a four-line file per system.
What survives is the part that was always right: an init is not a dependency in
0041's sense, because it is not installed, it is what the machine already is.

0048 named Docker as the container runtime. It is now docker or podman,
detected rather than chosen -- because adoption keeps what a machine already
has, so naming one contradicted a rule already decided. That row is the only
one of the five that names two, and the record now says why.

0060 claimed the bundle is portable across operating systems. Its mechanism is;
its contents are not -- package names, unit names, service names all differ, so
an Arch host embeds an Arch bundle. That was my error, and it is the exact
confusion behind the question that found it.

The design layer had the same drift: 07 and 09 said "Docker" where they meant a
container runtime, 09 said systemd restarts the host after an upgrade when the
launcher does, and both install snippets assumed Arch. They now show Alpine and
Arch side by side, which makes the point better than prose did -- step 1
differs per system, step 2 never does.

Checked and NOT changed: 0047's "the vocabulary grows by one shape" is a claim
about the rate, not the count, and is still true. 0037 lists docker among tools
the host manages, which it does. 0041 says nothing about either.

03-DESIGN/01-to-be/05-the-node-host.md

@@ -13,6 +13,7 @@ decisions:
   - 02-DECISIONS/0041-the-host-depends-on-nothing.md
   - 02-DECISIONS/0043-a-declaration-is-an-ordered-list-of-owned-resources.md
   - 02-DECISIONS/0057-the-host-is-a-root-service-installed-as-a-package.md
+  - 02-DECISIONS/0060-the-host-is-built-per-operating-system.md
   - 02-DECISIONS/0061-the-host-asks-an-init-for-start-and-restart.md
 ---
 
@@ -131,14 +132,18 @@ manages units and runs containers.
 Two steps, and there is nothing else:
 
 ```
-# 1 — put the host on the machine
-pacman -S nox-mesh-host
-systemctl enable --now nox-mesh-host
+# 1 — put the host on the machine, in that machine's own idiom
+apk add nox-mesh-host  &&  rc-update add nox-mesh-host  &&  rc-service nox-mesh-host start
+pacman -S nox-mesh-host  &&  systemctl enable --now nox-mesh-host
 
-# 2 — hand it the mesh
+# 2 — hand it the mesh. The same on every machine.
 nox-mesh-host enrol --token <one-time token>
 ```
 
+**Step 1 differs per system and step 2 never does**, which is the shape of
+[ADR 0060](../../02-DECISIONS/0060-the-host-is-built-per-operating-system.md): the package
+manager and the init file are the system's, and everything after them is the mesh's.
+
 The token carries the broker's address, the fingerprint to expect, and the right to join
 ([ADR 0051](../../02-DECISIONS/0051-the-enrolment-token-carries-the-mesh.md)). After that the
 node is in the mesh and takes declarations like every other one.