feat: 重写为 Tauri + React + TypeScript (v4.0)

完全移除旧 C+IUP 代码，改用 Tauri 2.x + React 19 + TypeScript + Rust 技术栈重写。
功能与 v3.1 完全等价：

- React 前端：Tailwind CSS 4、Zustand 状态管理、i18next 国际化
- Rust 后端：winreg 注册表读写、Win32 API FFI 调用
- 核心逻辑：StringList、UndoRedoManager、PathManager、Import/Export
- 深色模式、中英文切换、键盘快捷键、合并预览
- 66 个 Vitest 单元测试

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tests/unit/import-export.test.ts

@@ -0,0 +1,146 @@
+import { describe, it, expect } from 'vitest';
+import {
+  exportToJson,
+  exportToCsv,
+  importFromJson,
+  importFromCsv,
+  importFromTxt,
+  importFromContent,
+  detectExportFormat,
+  flattenImportResult,
+} from '../../src/core/import-export';
+
+const sampleData = {
+  system: ['C:\\Windows', 'C:\\Program Files'],
+  user: ['C:\\Users\\me\\AppData'],
+};
+
+describe('exportToJson', () => {
+  it('导出结构化 JSON', () => {
+    const json = exportToJson(sampleData);
+    const parsed = JSON.parse(json);
+    expect(parsed.version).toBe('1.0');
+    expect(parsed.type).toBe('PathEditor');
+    expect(parsed.system).toEqual(sampleData.system);
+    expect(parsed.user).toEqual(sampleData.user);
+    expect(parsed.exported).toBeDefined();
+  });
+});
+
+describe('importFromJson', () => {
+  it('正确导入 JSON', () => {
+    const json = JSON.stringify(sampleData);
+    const result = importFromJson(json);
+    expect(result.system).toEqual(sampleData.system);
+    expect(result.user).toEqual(sampleData.user);
+  });
+
+  it('过滤空字符串', () => {
+    const json = JSON.stringify({ system: ['C:\\', '', '  '], user: [] });
+    const result = importFromJson(json);
+    expect(result.system).toEqual(['C:\\']);
+  });
+});
+
+describe('exportToCsv', () => {
+  it('导出 CSV 含 BOM', () => {
+    const csv = exportToCsv(sampleData);
+    expect(csv.startsWith('')).toBe(true);
+    expect(csv).toContain('type,path');
+    expect(csv).toContain('system,C:\\Windows');
+    expect(csv).toContain('user,C:\\Users\\me\\AppData');
+  });
+
+  it('CSV 字段转义', () => {
+    const data = { system: ['C:\\Path,with,commas'], user: [] };
+    const csv = exportToCsv(data);
+    expect(csv).toContain('"C:\\Path,with,commas"');
+  });
+
+  it('CSV 双引号转义', () => {
+    const data = { system: ['Path with "quotes"'], user: [] };
+    const csv = exportToCsv(data);
+    expect(csv).toContain('"Path with ""quotes"""');
+  });
+});
+
+describe('importFromCsv', () => {
+  it('正确导入 CSV', () => {
+    const csv = 'type,path\nsystem,C:\\Windows\nuser,C:\\AppData\n';
+    const result = importFromCsv(csv);
+    expect(result.system).toEqual(['C:\\Windows']);
+    expect(result.user).toEqual(['C:\\AppData']);
+  });
+
+  it('跳过未知类型', () => {
+    const csv = 'type,path\nother,C:\\Unknown\nsystem,C:\\Valid';
+    const result = importFromCsv(csv);
+    expect(result.system.length).toBe(1);
+    expect(result.user.length).toBe(0);
+  });
+
+  it('处理带引号的 CSV 字段', () => {
+    const csv = 'type,path\nsystem,"C:\\Path,With,Commas"';
+    const result = importFromCsv(csv);
+    expect(result.system).toEqual(['C:\\Path,With,Commas']);
+  });
+});
+
+describe('importFromTxt', () => {
+  it('逐行导入，跳过注释和空行', () => {
+    const txt = '# 这是注释\nC:\\Windows\n\nD:\\Projects\n# 另一个注释';
+    const paths = importFromTxt(txt);
+    expect(paths).toEqual(['C:\\Windows', 'D:\\Projects']);
+  });
+
+  it('跳过 BOM', () => {
+    const txt = 'C:\\Windows';
+    const paths = importFromTxt(txt);
+    expect(paths).toEqual(['C:\\Windows']);
+  });
+});
+
+describe('importFromContent', () => {
+  it('根据扩展名选择格式', () => {
+    const csvContent = 'type,path\nsystem,C:\\Test';
+    const jsonContent = JSON.stringify({ system: ['C:\\Test'], user: [] });
+    const txtContent = 'C:\\Test';
+
+    expect(importFromContent(csvContent, 'test.csv').system).toEqual(['C:\\Test']);
+    expect(importFromContent(jsonContent, 'test.json').system).toEqual(['C:\\Test']);
+    expect(importFromContent(txtContent, 'test.txt').system).toEqual(['C:\\Test']);
+  });
+});
+
+describe('detectExportFormat', () => {
+  it('.csv 检测为 CSV', () => {
+    expect(detectExportFormat('data.CSV')).toBe('csv');
+  });
+
+  it('其他扩展名检测为 JSON', () => {
+    expect(detectExportFormat('data.json')).toBe('json');
+    expect(detectExportFormat('data.txt')).toBe('json');
+  });
+});
+
+describe('flattenImportResult', () => {
+  const data = { system: ['S1'], user: ['U1'] };
+
+  it('仅系统', () => {
+    const r = flattenImportResult(data, 'system');
+    expect(r.system).toEqual(['S1']);
+    expect(r.user).toEqual([]);
+  });
+
+  it('仅用户', () => {
+    const r = flattenImportResult(data, 'user');
+    expect(r.system).toEqual([]);
+    expect(r.user).toEqual(['U1']);
+  });
+
+  it('两者都导入', () => {
+    const r = flattenImportResult(data, 'both');
+    expect(r.system).toEqual(['S1']);
+    expect(r.user).toEqual(['U1']);
+  });
+});