🐛 fix(security): 修复 macOS 无法打开应用及三平台依赖系统钥匙串的问题

- 密文存储：新增 dailysecret 本地存储引擎，连接/代理/AI 密钥不再依赖系统钥匙串
- 启动迁移：自动将已有钥匙串密文迁移到本地 JSON，用户无感知
- WebKit 迁移：从旧版 Wails WebKit LocalStorage 中恢复连接与代理数据
- DMG 修复：移除 --sandbox-safe 避免扩展属性污染签名，新增 xattr 清理与签名校验
- 安全适配：钥匙串不可用时标记完成而非回滚，消除无钥匙串环境下的阻塞
- 出口脱敏：所有连接/代理 API 返回前统一 sanitize 防止密文泄漏

frontend/src/utils/appVersionDisplay.test.ts

@@ -0,0 +1,21 @@
+import { describe, expect, it } from 'vitest';
+
+import { resolveAboutDisplayVersion } from './appVersionDisplay';
+
+describe('resolveAboutDisplayVersion', () => {
+  it('shows fixed dev version for development build', () => {
+    expect(resolveAboutDisplayVersion('development', '0.6.5')).toBe('0.0.1-dev');
+  });
+
+  it('shows fixed dev version for wails dev build type', () => {
+    expect(resolveAboutDisplayVersion('dev', '0.6.5')).toBe('0.0.1-dev');
+  });
+
+  it('keeps real version for non-development builds', () => {
+    expect(resolveAboutDisplayVersion('production', '0.6.5')).toBe('0.6.5');
+  });
+
+  it('falls back to unknown when version is empty outside development', () => {
+    expect(resolveAboutDisplayVersion('production', '')).toBe('未知');
+  });
+});