feat(iace): Klaerungen Phase 2 — Sidebar-Counter + CSV-Export + Hazard-Banner

Three pieces complete the Klaerungen UX:

1. Sidebar-Counter: layout.tsx polls /clarifications and shows a
   colored open-count badge on the "Klaerungen" nav item. Refreshes
   whenever the user changes route.

2. CSV-Export: new backend endpoint
   GET /sdk/v1/iace/projects/:id/clarifications.csv produces a UTF-8-
   BOM-prefixed semicolon-separated CSV (Excel-friendly) with ID,
   Quelle, Kategorie, Frage, Status, Antwort, Begruendung, Bearbeiter,
   answered_at, anzahl Gefaehrdungen, Gefaehrdungs-Namen, Norm-Refs.
   Frontend Klaerungen-Seite bekommt einen "CSV-Export"-Button.

3. Hazard-Banner statt Fragentext im Benchmark-Detail: the previous
   bulleted clarification list was duplicated across 48 hazards for a
   single FANUC question. Phase 2 replaces it with a compact status
   badge — "N offene Klaerung(en) — Klaerungen-Seite oeffnen" (orange)
   or "Alle N Klaerungen beantwortet" (green) with a direct link.

Backend cleanup: iace_handler_init.go no longer appends the "Mit
Anlagenbauer zu klaeren" block to Hazard.Description. The description
stays focused on the scenario; clarifications live in the dedicated
endpoint and answers persist across re-inits via project.metadata.
The aggregated "Referenzierte Normen" line on the hazard is kept.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

admin-compliance/app/sdk/iace/layout.tsx

@@ -116,6 +116,23 @@ export default function IACELayout({ children }: { children: React.ReactNode })
   const [variantInfo, setVariantInfo] = React.useState<{
     parentProjectId?: string; parentName?: string; variantCount?: number
   }>({})
+  const [openClarifications, setOpenClarifications] = React.useState<number | null>(null)
+
+  // Poll the clarifications endpoint so the sidebar always shows the
+  // current "offene Klaerungen" counter. Refresh whenever the user
+  // navigates back to this layout (i.e. when pathname changes).
+  React.useEffect(() => {
+    if (!projectId) return
+    let cancelled = false
+    fetch(`/api/sdk/v1/iace/projects/${projectId}/clarifications`)
+      .then(r => r.ok ? r.json() : null)
+      .then(d => {
+        if (cancelled || !d || typeof d.open_count !== 'number') return
+        setOpenClarifications(d.open_count)
+      })
+      .catch(() => {})
+    return () => { cancelled = true }
+  }, [projectId, pathname])
 
   React.useEffect(() => {
     if (!projectId) return
@@ -219,7 +236,15 @@ export default function IACELayout({ children }: { children: React.ReactNode })
                 }`}
               >
                 <NavIcon icon={item.icon} className="w-4 h-4 flex-shrink-0" />
-                <span className="truncate">{item.label}</span>
+                <span className="truncate flex-1">{item.label}</span>
+                {item.id === 'clarifications' && openClarifications !== null && openClarifications > 0 && (
+                  <span
+                    className="ml-auto inline-flex items-center justify-center min-w-[20px] px-1.5 py-0.5 text-[10px] font-semibold rounded-full bg-orange-100 text-orange-800 dark:bg-orange-900/40 dark:text-orange-300"
+                    title={`${openClarifications} offene Klärung${openClarifications === 1 ? '' : 'en'}`}
+                  >
+                    {openClarifications}
+                  </span>
+                )}
               </Link>
             ))}
           </nav>