refactor: Entscheider-Kategorie als Einzelauswahl (Radio)

- Nur noch eine Kategorie gleichzeitig wählbar (Array → einzelner Wert)
- ceo-Label: "CEO / Owner / President / Founder" mit Empfohlen-Badge
- API-Aufruf sendet [category] statt categories[]
- Überflüssige Validierungen entfernt

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/maps/page.tsx

@@ -17,12 +17,12 @@ import type { DecisionMakerCategory } from "@/lib/services/anymailfinder";
 import type { ExportRow } from "@/lib/utils/csv";
 import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select";
 
-const CATEGORY_OPTIONS: { value: DecisionMakerCategory; label: string }[] = [
-  { value: "ceo", label: "CEO / Inhaber / Gründer" },
-  { value: "operations", label: "COO / Geschäftsführung" },
-  { value: "engineering", label: "CTO / Technik" },
-  { value: "marketing", label: "CMO / Marketing" },
-  { value: "finance", label: "CFO / Finanzen" },
+const CATEGORY_OPTIONS: { value: DecisionMakerCategory; label: string; recommended?: boolean }[] = [
+  { value: "ceo", label: "CEO / Owner / President / Founder", recommended: true },
+  { value: "operations", label: "COO" },
+  { value: "engineering", label: "CTO" },
+  { value: "marketing", label: "CMO" },
+  { value: "finance", label: "CFO" },
   { value: "sales", label: "Vertriebsleiter" },
 ];
 
@@ -55,7 +55,7 @@ export default function MapsPage() {
   const [regionInput, setRegionInput] = useState("");
   const [maxResults, setMaxResults] = useState("60");
   const [enrichEmails, setEnrichEmails] = useState(true);
-  const [categories, setCategories] = useState<DecisionMakerCategory[]>(["ceo"]);
+  const [category, setCategory] = useState<DecisionMakerCategory>("ceo");
   const [stage, setStage] = useState<Stage>("idle");
   const [jobId, setJobId] = useState<string | null>(null);
   const [progress, setProgress] = useState({ current: 0, total: 0, phase: "" });
@@ -78,8 +78,7 @@ export default function MapsPage() {
   const removeRegion = (r: string) => setRegions(prev => prev.filter(x => x !== r));
 
   const startJob = async () => {
-    if (!keyword.trim()) return toast.error("Enter a search keyword");
-    if (!categories.length && enrichEmails) return toast.error("Select at least one email category");
+    if (!keyword.trim()) return toast.error("Suchbegriff eingeben");
 
     setStage("running");
     setResults([]);
@@ -93,7 +92,7 @@ export default function MapsPage() {
           queries,
           maxResultsPerQuery: Number(maxResults),
           languageCode: "de",
-          categories,
+          categories: [category],
           enrichEmails,
         }),
       });
@@ -354,16 +353,17 @@ export default function MapsPage() {
             {CATEGORY_OPTIONS.map(opt => (
               <button
                 key={opt.value}
-                onClick={() => setCategories(prev =>
-                  prev.includes(opt.value) ? prev.filter(c => c !== opt.value) : [...prev, opt.value]
-                )}
-                className={`px-3 py-1.5 rounded-lg text-sm font-medium border transition-all ${
-                  categories.includes(opt.value)
+                onClick={() => setCategory(opt.value)}
+                className={`flex items-center gap-2 px-3 py-1.5 rounded-lg text-sm font-medium border transition-all ${
+                  category === opt.value
                     ? "bg-green-500/20 text-green-300 border-green-500/40"
                     : "bg-[#0d0d18] text-gray-400 border-[#2e2e3e] hover:border-green-500/30"
                 }`}
               >
                 {opt.label}
+                {opt.recommended && (
+                  <span className="text-[10px] bg-green-500/30 text-green-300 px-1.5 py-0.5 rounded font-semibold">Empfohlen</span>
+                )}
               </button>
             ))}
           </div>
@@ -380,7 +380,7 @@ export default function MapsPage() {
         {stage === "idle" || stage === "failed" ? (
           <Button
             onClick={startJob}
-            disabled={!keyword.trim() || (!categories.length && enrichEmails)}
+            disabled={!keyword.trim()}
             className="bg-gradient-to-r from-green-500 to-blue-600 hover:from-green-600 hover:to-blue-700 text-white font-medium px-8 shadow-lg hover:shadow-green-500/25 transition-all"
           >
             <MapPin className="w-4 h-4 mr-2" />