Initial commit: Developer Tools MVP with visual editor

- Complete React app with 7 developer tools
- JSON Tool with visual structured editor
- Serialize Tool with visual structured editor
- URL, Base64, CSV/JSON, Beautifier, Diff tools
- Responsive navigation with dropdown menu
- Dark/light mode toggle
- Mobile-responsive design with sticky header
- All tools working with copy/paste functionality

node_modules/@jest/reporters/build/DefaultReporter.d.ts

@@ -0,0 +1,33 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+/// <reference types="node" />
+import type { AggregatedResult, TestCaseResult, TestResult } from '@jest/test-result';
+import type { Config } from '@jest/types';
+import BaseReporter from './BaseReporter';
+import type { ReporterOnStartOptions, Test } from './types';
+export default class DefaultReporter extends BaseReporter {
+    private _clear;
+    private _err;
+    protected _globalConfig: Config.GlobalConfig;
+    private _out;
+    private _status;
+    private _bufferedOutput;
+    static readonly filename: string;
+    constructor(globalConfig: Config.GlobalConfig);
+    protected __wrapStdio(stream: NodeJS.WritableStream | NodeJS.WriteStream): void;
+    forceFlushBufferedOutput(): void;
+    protected __clearStatus(): void;
+    protected __printStatus(): void;
+    onRunStart(aggregatedResults: AggregatedResult, options: ReporterOnStartOptions): void;
+    onTestStart(test: Test): void;
+    onTestCaseResult(test: Test, testCaseResult: TestCaseResult): void;
+    onRunComplete(): void;
+    onTestResult(test: Test, testResult: TestResult, aggregatedResults: AggregatedResult): void;
+    testFinished(config: Config.ProjectConfig, testResult: TestResult, aggregatedResults: AggregatedResult): void;
+    printTestFileHeader(_testPath: Config.Path, config: Config.ProjectConfig, result: TestResult): void;
+    printTestFileFailureMessage(_testPath: Config.Path, _config: Config.ProjectConfig, result: TestResult): void;
+}