Mobilfunk: Feld "Mobilfunknetz" unter Anbieter & Tarif

Neues Dropdown "Mobilfunknetz" in der Anbieter-&-Tarif-Karte, nur
sichtbar bei Vertragstyp Mobilfunk. Optionen: Bitte auswählen (leer),
Telekom, Vodafone, Telefónica.

Neues Feld MobileContractDetails.mobileNetwork (String nullable,
speichert TELEKOM/VODAFONE/TELEFONICA) + idempotente Migration
(ADD COLUMN IF NOT EXISTS). String statt Enum, damit weitere Netze
ohne Migration ergänzbar sind. Anzeige in der Vertragsansicht mit
lesbarem Netz-Namen.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/pages/contracts/ContractDetail.tsx

@@ -3077,6 +3077,12 @@ export default function ContractDetail() {
       {c.mobileDetails && (
         <Card className="mb-6" title="Mobilfunk-Details">
           <dl className="grid grid-cols-2 md:grid-cols-4 gap-4">
+            {c.mobileDetails.mobileNetwork && (
+              <div>
+                <dt className="text-sm text-gray-500">Mobilfunknetz</dt>
+                <dd>{({ TELEKOM: 'Telekom', VODAFONE: 'Vodafone', TELEFONICA: 'Telefónica' } as Record<string, string>)[c.mobileDetails.mobileNetwork] || c.mobileDetails.mobileNetwork}</dd>
+              </div>
+            )}
             {c.mobileDetails.dataVolume && (
               <div>
                 <dt className="text-sm text-gray-500">Datenvolumen</dt>

frontend/src/pages/contracts/ContractForm.tsx

@@ -345,6 +345,7 @@ export default function ContractForm() {
         activationCode: c.internetDetails?.activationCode || '',
         // Mobile details
         requiresMultisim: c.mobileDetails?.requiresMultisim || false,
+        mobileNetwork: c.mobileDetails?.mobileNetwork || '',
         dataVolume: c.mobileDetails?.dataVolume || '',
         includedMinutes: c.mobileDetails?.includedMinutes || '',
         includedSMS: c.mobileDetails?.includedSMS || '',
@@ -656,6 +657,7 @@ export default function ContractForm() {
     if (data.type === 'MOBILE') {
       contractData.mobileDetails = {
         requiresMultisim: data.requiresMultisim || false,
+        mobileNetwork: emptyToNull(data.mobileNetwork),
         dataVolume: data.dataVolume ? parseFloat(data.dataVolume) : null,
         includedMinutes: safeParseInt(data.includedMinutes) ?? null,
         includedSMS: safeParseInt(data.includedSMS) ?? null,
@@ -1019,6 +1021,18 @@ export default function ContractForm() {
               options={availableTariffs.map((t) => ({ value: t.id, label: t.name }))}
               disabled={!selectedProviderId}
             />
+            {contractType === 'MOBILE' && (
+              <Select
+                label="Mobilfunknetz"
+                {...register('mobileNetwork')}
+                options={[
+                  { value: 'TELEKOM', label: 'Telekom' },
+                  { value: 'VODAFONE', label: 'Vodafone' },
+                  { value: 'TELEFONICA', label: 'Telefónica' },
+                ]}
+                placeholder="Bitte auswählen"
+              />
+            )}
             <Input label="Kundennummer beim Anbieter" maxLength={100} {...register('customerNumberAtProvider')} />
             <Input label="Vertragsnummer beim Anbieter" maxLength={100} {...register('contractNumberAtProvider')} />
             <Input label="Auftragsnummer bei Vertriebsplattform" maxLength={100} {...register('orderNumberAtSalesPlatform')} />

frontend/src/types/index.ts

@@ -588,6 +588,8 @@ export interface MobileContractDetails {
   id: number;
   contractId: number;
   requiresMultisim?: boolean;
+  /** Physisches Mobilfunknetz: TELEKOM | VODAFONE | TELEFONICA (oder null). */
+  mobileNetwork?: string | null;
   dataVolume?: number;
   includedMinutes?: number;
   includedSMS?: number;