Serialize project to json

src/Tools/tim_tool/src/gui/file_tab/callbacks.rs

@@ -95,7 +95,14 @@ pub(super) fn on_save_project_clicked(tim_manager: MutexTIMManager) -> impl FnMu
             project.push(cur_job);
         }
 
-        Err(Error::from_text(format!("Adding {:?} jobs", project)))
+        let string = match serde_json::to_string(&project) {
+            Ok(string) => string,
+            Err(error) => {
+                return Err(Error::from_error(error));
+            }
+        };
+
+        Err(Error::from_text(format!("Adding {} jobs", string)))
     }
 }