feat: add template upload/download/delete endpoints

Belge Şablonları now stores real files: POST /api/templates/upload
(multer -> Supabase Storage under templates/<user>/, then a templates
row), GET /api/templates/:id/download-url (short-lived signed URL),
and DELETE /api/templates/:id. Mounted at /api/templates.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/routes/template.routes.ts

@@ -0,0 +1,13 @@
+import { Router } from 'express';
+import multer from 'multer';
+import { requireAuth } from '../middleware/auth';
+import { uploadTemplate, getTemplateDownloadUrl, deleteTemplate } from '../controllers/template.controller';
+
+const router = Router();
+const upload = multer({ storage: multer.memoryStorage() });
+
+router.post('/upload', upload.single('file'), requireAuth, uploadTemplate);
+router.get('/:templateId/download-url', requireAuth, getTemplateDownloadUrl);
+router.delete('/:templateId', requireAuth, deleteTemplate);
+
+export default router;