Consolidate: 65 decision records to 52

Jochen: a normal application has 3-5 ADRs, maybe 10 for a large one, and we are
at 65. Fair, and the cause is mine -- I recorded every FINDING as a decision
rather than every fork in the road.

Two merges, both cases where one decision had been split across many records
because it was taken over several days rather than at once.

0019 absorbs ten records about how this repository works: what it is and that
it is public, the folder flow, the two design layers, the issue front door,
status in frontmatter, playbooks, the naming rule, the product name. Those were
never ten decisions -- they were one, seen from ten angles as the repository
took shape.

0016 absorbs the five about the lab: a node is a virtual machine, a router is
scenery, a scenario declares the underlay, a scenario is a closed address
space, and the two scenario classes. Same pattern -- one design, split by the
order it was worked out in.

The consolidated 0019 also raises the bar for what earns a record, since that
is what produced 65: a record is warranted when there is a genuine fork -- a
direction reversed, an alternative that will be proposed again, something
contested. A finding is not a decision, and a bug is certainly not. Everything
else belongs in the design document where the reasoning is actually read.

The checker earned its place here. Deleting nine records left 13 dangling links
across the repository and it named every one, including in AGENTS.md. Nothing
was found by reading.

Remaining clusters worth the same treatment: the host (8 records), delivery
(5), modules (6), connectivity (4), substrate and control plane (4). That would
be 52 down to roughly 30.

01-RESEARCH/009-migration/00-overview.md

@@ -4,7 +4,7 @@ initiated: 2026-08-23
 touches:
   - 01-RESEARCH/006-mesh-from-scratch/code-skeleton.md
   - 03-DESIGN/01-to-be/01-end-to-end-testing.md
-  - 02-DECISIONS/0016-a-lab-node-is-a-virtual-machine.md
+  - 02-DECISIONS/0016-the-lab.md
   - 03-DESIGN/00-as-is/00-overview.md
 became: []
 ---
@@ -28,7 +28,7 @@ Recorded because incremental is the reflex answer and it is wrong in this case.
   requirements — none of these can half-apply. Running both models at once means the old one's
   assumptions keep constraining the new one, which is how a migration becomes permanent.
 - **Nothing external depends on it.** No users outside the operator, no service level to hold.
-- **The lab exists precisely for this** ([ADR 0016](../../02-DECISIONS/0016-a-lab-node-is-a-virtual-machine.md)).
+- **The lab exists precisely for this** ([ADR 0016](../../02-DECISIONS/0016-the-lab.md)).
   A big-bang that has been rehearsed end to end, repeatedly, on identical machines is not the
   same risk as one performed for the first time on the real mesh. This is also why the lab is
   phase 0 rather than a verification step later: the new mesh is *developed* inside it, so by
@@ -70,7 +70,7 @@ than a discovery.
 
 | Phase | What | Done when |
 |---|---|---|
-| **0** | **Build the lab's bootstrap scenario** ([ADR 0029](../../02-DECISIONS/0029-the-labs-first-scenario-has-no-pipeline.md)) — virtual machines, a network, a way to place a binary, snapshot and reset. No forge, no coordinator, no pipeline. | A machine can be raised from nothing, reset, and raised again, repeatably. |
+| **0** | **Build the lab's bootstrap scenario** ([ADR 0016](../../02-DECISIONS/0016-the-lab.md)) — virtual machines, a network, a way to place a binary, snapshot and reset. No forge, no coordinator, no pipeline. | A machine can be raised from nothing, reset, and raised again, repeatably. |
 | A | Build tier 0, **inside the lab**. The host's interface first — it carries the skeleton's biggest unproven claim. | A bare machine becomes a managed node with no mesh present. |
 | B | Build tier 1 and 2. The bootstrap scenario grows into the full one by addition — the same machines, with more placed inside them. | The lab raises a full mesh from nothing, repeatedly, from pinned external artifacts. |
 | C | Enough of tier 3 to operate it. | The mesh can be driven without direct database access. |