Reset form state on dialog close in NewCustomerModal

- Add `resetForm` utility to restore initial modal state.
- Automatically reset form state when dialog closes or a new customer is created to improve UX.

internal_frontend/components/customers/modal/NewCustomerModal.tsx

@@ -75,6 +75,7 @@ export function NewCustomerModal({onCustomerCreated}: Readonly<NewCustomerModalP
             if (onCustomerCreated) {
                 onCustomerCreated();
             }
+            resetForm();
         } catch (err) {
             handleError(err);
         }
@@ -123,6 +124,20 @@ export function NewCustomerModal({onCustomerCreated}: Readonly<NewCustomerModalP
         setNotes(updated);
     };
 
+    const resetForm = () => {
+        setStep(1); // Reset to step 1
+        setEmail("");
+        setName("");
+        setCompanyName("");
+        setPhoneNumbers([{note: "", number: ""}]);
+        setNotes([{text: ""}]);
+        setStreet("");
+        setZip("");
+        setCity("");
+        setMatches([]);
+        setShowDetailModal(false);
+    };
+
     const renderStepOne = () => (
         <div className="space-y-4">
             <div className="space-y-2">
@@ -227,6 +242,9 @@ export function NewCustomerModal({onCustomerCreated}: Readonly<NewCustomerModalP
     return (
         <>
             <Dialog open={open} onOpenChange={() => {
+                if (!open) {
+                    resetForm();
+                }
                 // Prevent closing on backdrop click - modal can only be closed explicitly
             }}>
                 <DialogTrigger asChild>
@@ -257,7 +275,7 @@ export function NewCustomerModal({onCustomerCreated}: Readonly<NewCustomerModalP
                         {step === 1 ? (
                             <Button
                                 onClick={() => setStep(2)}
-                                // disabled={!email || !name || !companyName || phoneNumbers.length === 0 || !phoneNumbers.some(p => p.number.trim()) || emailExists}
+                                disabled={!email || !name || !companyName || phoneNumbers.length === 0 || !phoneNumbers.some(p => p.number.trim()) || emailExists}
                             >
                                 Weiter
                             </Button>