Update test framework: fix run_tests.py to support all test files, add auto-import-check for test files

node_modules/jsondiffpatch/lib/contexts/diff.d.ts

@@ -0,0 +1,14 @@
+import Context from './context.js';
+import type { Delta } from '../types.js';
+declare class DiffContext extends Context<Delta> {
+    left: unknown;
+    right: unknown;
+    pipe: 'diff';
+    leftType?: string;
+    rightType?: string;
+    leftIsArray?: boolean;
+    rightIsArray?: boolean;
+    constructor(left: unknown, right: unknown);
+    setResult(result: Delta): this;
+}
+export default DiffContext;