A run rebuilds what it tests, and leaves a receipt saying what it covered

The danger is not that the suite breaks. It is that nobody notices it
stopped running (novox/hq 04-ISSUES/005). The harness this replaces had
not built for two and a half months and nothing said so — and this suite
needs a hypervisor, so it inherits exactly that: it runs when somebody
remembers, and remembering is not a mechanism.

So running, recording, and rebuilding are one act:

- the host binary, control-plane image and builder are rebuilt from
  source first. The last two both parse manifests; building one and not
  the other left a binary eleven hours old refusing a field the mesh had
  just renamed, found by a full run.
- a receipt lands in XDG state — outside git, because the question is
  whether *this machine* has run it, and a receipt in git would be a
  claim about everybody's machine made by whoever committed last.
- `last-run` judges it and exits non-zero when it no longer counts.

Three faults found by running the thing rather than reading it, each now
held by a test confirmed to fail without it:

- counted() passed every test while parsing nothing. The runner colours
  its summary even into a pipe; the fixtures were clean text that had
  been imagined rather than captured. A fixture that agrees with the
  mistake proves the mistake.
- a receipt for `suite test/lastrun.test.ts` was indistinguishable from
  one for the real thing — 005's own symptom, rebuilt inside its remedy.
  The receipt now records what ran.
- a tree with uncommitted work reported the bare commit, claiming
  coverage of code nobody can check out. Nothing else could tell: the
  hash is identical either way.

Proven on real machines: 22/22, against all three repositories.

package.json

@@ -9,8 +9,9 @@
   "scripts": {
     "typecheck": "tsc --noEmit && tsc --noEmit -p tsconfig.test.json",
     "test": "node --test --experimental-strip-types 'test/*.test.ts'",
-    "test:integration": "node --test --test-concurrency=1 --experimental-strip-types 'test/integration/*.test.ts'",
-    "check": "npm run typecheck && npm test && npm run test:integration"
+    "test:integration": "node --experimental-strip-types src/cli.ts suite",
+    "check": "npm run typecheck && npm test && npm run test:integration",
+    "last-run": "node --experimental-strip-types src/cli.ts last-run"
   },
   "dependencies": {
     "yaml": "^2.6.0"