fix: templateService return format and Templates page array handling

- Updated templateService to return response.data like other services
- Added fallback to empty array in Templates.jsx to prevent map errors
- Ensures consistency across all service modules

frontend/src/pages/Templates.jsx

@@ -63,10 +63,11 @@ function Templates() {
     try {
       setLoading(true);
       const response = await templateService.getAll();
-      setTemplates(response.data);
+      setTemplates(response.data || []);
     } catch (error) {
       console.error('Failed to load templates:', error);
       alert('Şablonlar yüklenemedi');
+      setTemplates([]);
     } finally {
       setLoading(false);
     }

frontend/src/services/templateService.js

@@ -1,11 +1,29 @@
 import api from './api';
 
 export const templateService = {
-  getAll: () => api.get('/api/templates'),
-  getById: (id) => api.get(`/api/templates/${id}`),
-  create: (data) => api.post('/api/templates', data),
-  update: (id, data) => api.put(`/api/templates/${id}`, data),
-  delete: (id) => api.delete(`/api/templates/${id}`),
-  preview: (data) => api.post('/api/templates/preview', data),
+  getAll: async () => {
+    const response = await api.get('/api/templates');
+    return response.data;
+  },
+  getById: async (id) => {
+    const response = await api.get(`/api/templates/${id}`);
+    return response.data;
+  },
+  create: async (data) => {
+    const response = await api.post('/api/templates', data);
+    return response.data;
+  },
+  update: async (id, data) => {
+    const response = await api.put(`/api/templates/${id}`, data);
+    return response.data;
+  },
+  delete: async (id) => {
+    const response = await api.delete(`/api/templates/${id}`);
+    return response.data;
+  },
+  preview: async (data) => {
+    const response = await api.post('/api/templates/preview', data);
+    return response.data;
+  },
 };