add individual library scanning

src/app/api/scan/[id]/route.ts

@@ -0,0 +1,28 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { getLibrary } from '@/lib/libraries'
+import { isScanRunning, runSingleLibraryScan } from '@/lib/scanner'
+import { requireAdmin } from '@/lib/auth'
+
+export async function POST(
+  request: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const auth = await requireAdmin(request)
+  if (auth instanceof NextResponse) return auth
+
+  const { id } = await params
+
+  const library = getLibrary(id)
+  if (!library) {
+    return NextResponse.json({ error: 'Library not found' }, { status: 404 })
+  }
+
+  if (isScanRunning()) {
+    return NextResponse.json({ error: 'Scan already in progress' }, { status: 409 })
+  }
+
+  // Fire-and-forget
+  void runSingleLibraryScan(library)
+
+  return new NextResponse(null, { status: 202 })
+}