feature fixes

vite.config.ts

@@ -37,5 +37,35 @@ export default defineConfig({
   test: {
     include: ["src/**/*.test.ts"],
     environment: "node",
+
+    // The markdown suites are thousands of generated documents pushed through the writer inside one
+    // synchronous loop, and the worst of them holds a worker's event loop for the better part of
+    // half a minute even on a fast machine. Everything below exists because of that.
+    //
+    // A worker tells the main process about each test it starts, over an RPC call it then waits on,
+    // and that call is given sixty seconds before it gives up with `Timeout calling "onTaskUpdate"`.
+    // A test that blocks the loop cannot take delivery of the answer while it is running, so what
+    // the sixty seconds really bounds is the length of the slowest single test, not the round trip.
+    // Vitest does not expose that timeout, so the only lever left is keeping the tests from getting
+    // slower, and what makes them slower is contention. The default is one worker per core bar one,
+    // which on a two or three core hosted runner has the heaviest suites fighting each other and the
+    // main process for the same cores. Half the cores gives each worker a core to itself and still
+    // leaves one for the main process to answer on. This is a percentage rather than a number
+    // behind a CI check because it lands on the right answer for a two core runner, a three core
+    // one and a developer's laptop without anyone having to know which one the job got, and it
+    // costs nothing locally: the run is bounded by its slowest single file either way.
+    maxWorkers: "50%",
+
+    // Five seconds is the default and nothing in the markdown suites honours it. The slow tests
+    // pass their own timeout to `it` as a third argument. The merely slow-ish ones do not, and they
+    // are the ones that go red on a loaded runner having done nothing wrong. Thirty seconds is what
+    // most of the annotated tests already ask for, and it stays under the sixty the RPC allows, so
+    // this cannot itself cause the failure described above.
+    testTimeout: 30_000,
+    hookTimeout: 30_000,
+
+    // How long a worker is given to shut down before it is killed. Ten seconds is plenty when the
+    // machine is idle and is not when several forks are all winding up at once.
+    teardownTimeout: 30_000,
   },
 });