fix: Playwright API camelCase → snake_case (Python 版)

- getByPlaceholder → get_by_placeholder
- getByRole → get_by_role
- getByText → get_by_text
- getByTestId → get_by_test_id

tests/web/pages/base_page.py

@@ -6,8 +6,8 @@ Usage:
     class LoginPage(BasePage):
         def __init__(self, page):
             super().__init__(page)
-            self.phone_input = page.getByPlaceholder("请输入用户名")
-            self.login_btn = page.getByRole("button", name="登录")
+            self.phone_input = page.get_by_placeholder("请输入用户名")
+            self.login_btn = page.get_by_role("button", name="登录")
 """
 
 from datetime import datetime
@@ -38,7 +38,7 @@ class BasePage:
 
     def wait_for_text(self, text: str, timeout_ms: Optional[int] = None) -> None:
         """等待页面上出现指定文本。"""
-        expect(self.page.getByText(text)).to_be_visible(timeout=timeout_ms or self.timeout)
+        expect(self.page.get_by_text(text)).to_be_visible(timeout=timeout_ms or self.timeout)
 
     # ── 通用操作 ──