feat: add delete customer + fix auth form UX

- Backend: DELETE /api/customers/:id removes customer + extensions + logs
- Frontend: delete button on customer detail with confirmation
- Auth form: only sends espocrm_api_key when credentials are entered

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

dashboard/src/App.jsx

@@ -107,6 +107,12 @@ function CustomersTab() {
   const [selected, setSelected] = useState(null)
   const [showForm, setShowForm] = useState(false)
 
+  const deleteCustomer = async (id) => {
+    await fetch(`${API}/customers/${id}`, { method: 'DELETE' })
+    if (selected === id) setSelected(null)
+    reload()
+  }
+
   if (!customers) return <Loader />
   return (
     <div className="flex gap-6">
@@ -143,7 +149,7 @@ function CustomersTab() {
         </div>
       </div>
       <div className="flex-1 min-w-0">
-        {selected ? <CustomerDetail customerId={selected} /> : (
+        {selected ? <CustomerDetail customerId={selected} onDelete={() => deleteCustomer(selected)} /> : (
           <div className="bg-white rounded-xl p-12 text-center text-slate-400">
             <Icon name="touch_app" className="text-5xl mb-4 block" />
             <p className="font-medium">בחר לקוח מהרשימה</p>
@@ -226,7 +232,7 @@ function CustomerForm({ onDone, onCancel, customer }) {
   )
 }
 
-function CustomerDetail({ customerId }) {
+function CustomerDetail({ customerId, onDelete }) {
   const { data: customer, reload } = useFetch(`${API}/customers/${customerId}`)
   const { data: allExtensions } = useFetch(`${API}/extensions`)
   const [deploying, setDeploying] = useState(null)
@@ -366,6 +372,11 @@ function CustomerDetail({ customerId }) {
             title="עריכת לקוח">
             <Icon name="edit" className="text-lg" />
           </button>
+          <button onClick={() => { if (confirm('למחוק את הלקוח לצמיתות?')) onDelete() }}
+            className="p-2 text-slate-400 hover:text-red-600 hover:bg-red-50 rounded-lg transition-all"
+            title="מחיקת לקוח">
+            <Icon name="delete" className="text-lg" />
+          </button>
         </div>
       )}