fix: remove t from getDefaultAppState and allow name to be nullable (#7666)

* fix: remove t and allow name to be nullable

* pass name as required prop

* remove Unnamed

* pass name to excalidrawPlus as well for better type safe

* render once we have excalidrawAPI to avoid defaulting

* rename `getAppName` -> `getName` (temporary)

* stop preventing editing filenames when `props.name` supplied

* keep `name` as optional param for export functions

* keep `appState.name` on `props.name` state separate

* fix lint

* assertive first

* fix lint

* Add TODO

---------

Co-authored-by: dwelle <5153846+dwelle@users.noreply.github.com>

packages/excalidraw/data/json.ts

@@ -1,6 +1,7 @@
 import { fileOpen, fileSave } from "./filesystem";
 import { cleanAppStateForExport, clearAppStateForDatabase } from "../appState";
 import {
+  DEFAULT_FILENAME,
   EXPORT_DATA_TYPES,
   EXPORT_SOURCE,
   MIME_TYPES,
@@ -71,6 +72,8 @@ export const saveAsJSON = async (
   elements: readonly ExcalidrawElement[],
   appState: AppState,
   files: BinaryFiles,
+  /** filename */
+  name: string = appState.name || DEFAULT_FILENAME,
 ) => {
   const serialized = serializeAsJSON(elements, appState, files, "local");
   const blob = new Blob([serialized], {
@@ -78,7 +81,7 @@ export const saveAsJSON = async (
   });
 
   const fileHandle = await fileSave(blob, {
-    name: appState.name,
+    name,
     extension: "excalidraw",
     description: "Excalidraw file",
     fileHandle: isImageFileHandle(appState.fileHandle)