feat: 完成Tab④账号管理

- 新增 accounts 服务层，封装账号 CRUD、目录创建、端口分配与登录检测

- 接入 PySide6 账号管理 Tab：表格、账号弹窗、启动登录、后台检测登录

- 密码仅本地保存并在 UI 打码，表格不展示明文；不自动登录或填密码

- 增加顶部 Tab 栏防误点样式，扩大点击区域并高亮当前 Tab

- 补充账号服务和 GUI 单元测试，并同步架构、API、路由、任务和进度文档

tests/test_accounts.py

@@ -0,0 +1,142 @@
+import os
+import unittest
+from unittest import mock
+
+from _helpers import TempDirMixin
+
+from app import accounts
+from app import config as account_config
+
+
+class AccountsTests(TempDirMixin, unittest.TestCase):
+    def make_config(self, temp_dir):
+        return {
+            "chrome_path": "chrome.exe",
+            "user_data_root": os.path.join(temp_dir, "chrome_user_data_dir"),
+            "db_path": os.path.join(temp_dir, "cmshopee.db"),
+            "debug_port_range": [9222, 9224],
+        }
+
+    def test_create_account_stores_record_and_creates_user_data_dir(self):
+        with self.make_temp_dir() as temp_dir:
+            cfg = self.make_config(temp_dir)
+            account = accounts.create_account(
+                "主店",
+                "alias",
+                "https://seller.shopee.tw/portal/",
+                9222,
+                password="secret",
+                note="备注",
+                config=cfg,
+            )
+
+            self.assertEqual("主店", account.account_name)
+            self.assertEqual("alias", account.alias)
+            self.assertEqual("seller.shopee.tw", account.region_host)
+            self.assertEqual("alias_cdb6fdbe", account.slug)
+            self.assertTrue(os.path.isdir(account.user_data_dir))
+            self.assertEqual("******", accounts.mask_password(account.password))
+            self.assertEqual([account], accounts.list_accounts(config=cfg))
+
+        self.assert_removed(temp_dir)
+
+    def test_update_account_can_change_alias_and_rebuild_directory(self):
+        with self.make_temp_dir() as temp_dir:
+            cfg = self.make_config(temp_dir)
+            accounts.create_account("主店", "alias", debug_port=9222, config=cfg)
+
+            updated = accounts.update_account(
+                "alias",
+                "新主店",
+                "new alias",
+                "seller.shopee.tw",
+                9333,
+                password="new-secret",
+                note="新备注",
+                config=cfg,
+            )
+
+            self.assertEqual("new alias", updated.alias)
+            self.assertEqual(account_config.make_slug("new alias"), updated.slug)
+            self.assertEqual(9333, updated.debug_port)
+            self.assertTrue(os.path.isdir(updated.user_data_dir))
+            with self.assertRaises(accounts.AccountError):
+                accounts.get_account("alias", config=cfg)
+            self.assertEqual("new-secret", accounts.get_account("new alias", config=cfg).password)
+
+        self.assert_removed(temp_dir)
+
+    def test_next_debug_port_skips_existing_accounts(self):
+        with self.make_temp_dir() as temp_dir:
+            cfg = self.make_config(temp_dir)
+            accounts.create_account("店1", "a1", debug_port=9222, config=cfg)
+            accounts.create_account("店2", "a2", debug_port=9223, config=cfg)
+
+            self.assertEqual(9224, accounts.next_debug_port(config=cfg))
+
+        self.assert_removed(temp_dir)
+
+    def test_launch_for_login_only_launches_chrome(self):
+        with self.make_temp_dir() as temp_dir:
+            cfg = self.make_config(temp_dir)
+            account = accounts.create_account("主店", "alias", debug_port=9222, config=cfg)
+            process = object()
+
+            with mock.patch("app.accounts.chrome.launch_chrome", return_value=process) as launch:
+                result = accounts.launch_for_login("alias", config=cfg)
+
+            self.assertIs(process, result)
+            launch.assert_called_once_with(account, config=cfg)
+
+        self.assert_removed(temp_dir)
+
+    def test_detect_login_updates_last_login_at_when_logged_in(self):
+        with self.make_temp_dir() as temp_dir:
+            cfg = self.make_config(temp_dir)
+            accounts.create_account("主店", "alias", debug_port=9222, config=cfg)
+
+            with mock.patch(
+                "app.accounts.editor.login_status",
+                return_value={"logged_in": True, "reason": None},
+            ) as login_status:
+                status = accounts.detect_login("alias", timeout=1, config=cfg)
+
+            self.assertTrue(status["logged_in"])
+            login_status.assert_called_once()
+            self.assertIsNotNone(accounts.get_account("alias", config=cfg).last_login_at)
+
+        self.assert_removed(temp_dir)
+
+    def test_duplicate_alias_raises_clear_error(self):
+        with self.make_temp_dir() as temp_dir:
+            cfg = self.make_config(temp_dir)
+            accounts.create_account("店1", "alias", debug_port=9222, config=cfg)
+
+            with self.assertRaises(accounts.AccountError):
+                accounts.create_account("店2", "alias", debug_port=9223, config=cfg)
+
+        self.assert_removed(temp_dir)
+
+    def test_duplicate_debug_port_raises_clear_error(self):
+        with self.make_temp_dir() as temp_dir:
+            cfg = self.make_config(temp_dir)
+            accounts.create_account("店1", "a1", debug_port=9222, config=cfg)
+            accounts.create_account("店2", "a2", debug_port=9223, config=cfg)
+
+            with self.assertRaises(accounts.AccountError):
+                accounts.create_account("店3", "a3", debug_port=9222, config=cfg)
+            with self.assertRaises(accounts.AccountError):
+                accounts.update_account(
+                    "a2",
+                    "店2",
+                    "a2",
+                    "seller.shopee.tw",
+                    9222,
+                    config=cfg,
+                )
+
+        self.assert_removed(temp_dir)
+
+
+if __name__ == "__main__":
+    unittest.main()