ci: stabilize flaky Test job (cap nx parallelism + raise vitest timeouts) (#478)

* test(devtools): raise vitest timeouts to stop flaky component test:lib in CI

The component tests added in #472 render the full Solid + goober tree and take
1-4s locally. Shared CI runners are ~4x slower (the suite runs in ~8s locally
but ~31s in CI), which pushes individual tests past vitest's default 5s
testTimeout and causes intermittent `@tanstack/devtools:test:lib` failures
across unrelated PRs (e.g. #471, #477).

Raise testTimeout and hookTimeout to 30s for the devtools package so slow CI
runs have headroom. Fast unit tests are unaffected; a real hang still fails
(just after 30s instead of 5s).

* ci: cap nx parallelism to 3 to fix flaky Test job

nx.json sets `parallel: 5`, which is fine for local dev machines but
oversubscribes GitHub-hosted runners: each affected `test:lib` (vitest) and
`test:types` (tsc) task spawns its own worker pool, so 5 heavy tasks at once
exhaust CPU/RAM and intermittently stall or OOM-kill deterministic tasks. That
produced flaky failures across unrelated PRs (#471, #477, #478) that pass on a
plain re-run.

The team already pins `test:e2e` to `--parallel=1` for the same reason; cap the
Test job's nx parallelism via NX_PARALLEL=3 (CI-only, leaves local dev at 5).
Combined with the raised vitest timeouts, this keeps tasks within the runner's
budget.

Author: AlemTuzlak

.github/workflows/pr.yml

@@ -9,6 +9,12 @@ concurrency:
 
 env:
   NX_CLOUD_ACCESS_TOKEN: ${{ secrets.NX_CLOUD_ACCESS_TOKEN }}
+  # nx.json sets parallel: 5 for local dev machines. GitHub-hosted runners have
+  # far fewer cores/RAM, and each test:lib (vitest) / test:types (tsc) task
+  # spawns its own worker pool. Running 5 such heavy tasks at once oversubscribes
+  # the runner and intermittently OOM-kills or stalls tasks, producing flaky
+  # failures that pass on re-run. Cap CI parallelism to keep tasks within budget.
+  NX_PARALLEL: 3
 
 permissions:
   contents: read

packages/devtools/vite.config.ts

@@ -13,6 +13,12 @@ const config = defineConfig({
     environment: 'jsdom',
     setupFiles: ['./tests/test-setup.ts'],
     globals: true,
+    // Component tests render the full Solid + goober tree (see src/**/*.test.tsx).
+    // These take 1-4s locally but run on shared CI runners that are ~4x slower,
+    // pushing individual tests past vitest's default 5s timeout and causing
+    // flaky `test:lib` failures. Give them headroom; fast tests are unaffected.
+    testTimeout: 30_000,
+    hookTimeout: 30_000,
   },
 })