test(checks): #44 doctor hardware section — headless guard

Extend checks.doctor: the bare test VM lacks every probe tool, so the
healthy nomarchy-doctor run drives all six hardware checks in skip mode.
Assert the self-gated skip rows appear (NetworkManager, fingerprint,
fwupd, VA-API) and the sheet still exits 0 — proving the section runs
without erroring under set -euo pipefail. No node changes.

Verified V2: nix build .#checks.x86_64-linux.doctor passes. Closes #44.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

agent/JOURNAL.md

@@ -17,6 +17,18 @@ Template:
 
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+## 2026-07-09 — #44 V2: checks.doctor guards the hardware section
+- **Task:** close #44's V2 (was V1 + real-hw smoke). Extend `checks.doctor`.
+- **Did:** The bare test VM has none of the probe tools, so the existing
+  healthy `nomarchy-doctor` run already drives all six hardware checks in
+  skip mode. Added assertions that the skip rows appear (NetworkManager,
+  fingerprint, fwupd, VA-API) and the sheet still exits 0 — i.e. the section
+  runs without erroring under `set -euo pipefail`. No node changes (no closure
+  bump); the *fires* paths keep the agent's real-hardware evidence.
+- **Verified:** **V2** — `nix build .#checks.x86_64-linux.doctor` passes.
+  Permanent headless regression guard now in place.
+- **Next:** #43 System-menu render (Firmware row).
+
 ## 2026-07-09 — #53 theme previews + neon-glass quarantine
 - **Task:** NEXT #53 — capture the last two missing previews + resolve the
   neon-glass broken whole-swap. Product call: **quarantine**.