platform/cmd/webui: add a scriptable test-scenario engine, load scenarios from blackbox USB, GPU status detail inventory fallback

Investigating the CG480-S6053 reboot needed a way to run an ad-hoc load
(nvbandwidth across a specific GPU set) while sampling IPMI/nvidia-smi
telemetry in the background — without hardcoding a one-off test into the
SAT pack code for a single investigation.

- audit/internal/platform/scenario.go: ScenarioSpec/ScenarioJob (JSON,
  no new dependency) + System.RunScenario. "command" jobs run sequential
  or parallel (per-job "parallel" flag); "sampler" jobs run concurrently
  in the background on their own interval until every command job
  finishes or the scenario's timeout elapses. "{{gpus}}" in a command's
  cmd is substituted from that job's gpu_indices. Command jobs are wired
  through the same satJobBoundaryHook/satSyncBracketHook seams the SAT
  job runner uses, so a scenario run gets the same durability treatment
  (evidence that a risky command started/finished reaches blackbox before
  a possible crash, not just whatever streamed to the RAM-backed export
  dir).
- export.go: ReadScenarioFromRemovableMedia mounts each removable target
  looking for scenarios/<name>.json — an air-gapped engineer can author a
  scenario elsewhere, drop it under scenarios/ on the same USB stick
  already plugged in for blackbox, and run it with no network path onto
  the host.
- cmd/bee: new `bee run <file.json|name>` (bare name = looked up on
  removable media); `bee scenario run <arg>` kept as a longer alias.
- scenarios/nvbandwidth-all-gpu-power-watch.json: the scenario that
  reproduced the actual reboot (full nvbandwidth across all GPUs, which
  crashed, vs. clean per-socket passes), with IPMI sensor + GPU power/temp
  sampling for a power-delivery correlation check.

Also: webui/page_topo.go — the /topo page's component-status-detail modal
(GET /api/component-detail/{type}) showed "No status data recorded yet"
for any component type ComponentStatusDB has no history for yet (e.g. GPU
before a SAT run this boot), even though the topology card for the same
component already showed "N OK" from the audit inventory snapshot.
inventoryFallbackRecords now synthesizes records from that same inventory
snapshot when StatusDB is empty, using the same device classifiers
(isGPUDeviceClass etc.) and severity mapping (classifyTopoSeverity) the
topology card itself uses, so the two views never disagree.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

audit/internal/webui/pages.go

@@ -1160,7 +1160,10 @@ func renderSparkline(history []app.ComponentStatusEntry) string {
 
 // renderComponentDetail renders a modal content fragment for one component type.
 // Called by handleAPIComponentDetail and displayed inside #component-detail-dialog.
-func renderComponentDetail(title string, records []app.ComponentStatusRecord) string {
+// fromInventory marks that records were synthesized from the audit inventory
+// snapshot (no ComponentStatusDB history yet) rather than real SAT/watchdog
+// observations — see inventoryFallbackRecords.
+func renderComponentDetail(title string, records []app.ComponentStatusRecord, fromInventory bool) string {
 	var b strings.Builder
 	fmt.Fprintf(&b, `<div style="padding:20px 24px 0">`)
 	fmt.Fprintf(&b, `<div style="display:flex;align-items:center;justify-content:space-between;margin-bottom:16px">`)
@@ -1174,6 +1177,10 @@ func renderComponentDetail(title string, records []app.ComponentStatusRecord) st
 		return b.String()
 	}
 
+	if fromInventory {
+		b.WriteString(`<p style="color:var(--muted);font-size:12px;margin-top:-8px;margin-bottom:16px">No SAT-test history yet — showing latest inventory snapshot.</p>`)
+	}
+
 	sort.Slice(records, func(i, j int) bool {
 		return records[i].ComponentKey < records[j].ComponentKey
 	})