refactor: remove environment variable imports from auth module

- Remove os, dotenv, and pathlib imports
- Remove module-level environment setup code
- Prepare for pure function implementation

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

utils/auth.py

@@ -2,25 +2,8 @@
 Authentication module - Responsible for Yonyou BIP system login and logout operations
 """
 
-import os
-from pathlib import Path
 from playwright.sync_api import Playwright, Browser, BrowserContext, Page, Frame
 
-# Load environment variables
-from dotenv import load_dotenv
-
-# Get project root directory
-BASE_DIR = Path(__file__).resolve().parent.parent
-
-# Load .env file
-env_path = BASE_DIR / ".env"
-load_dotenv(env_path)
-
-# Configure Playwright browser path
-browsers_path = os.getenv("PLAYWRIGHT_BROWSERS_PATH")
-if browsers_path:
-    os.environ["PLAYWRIGHT_BROWSERS_PATH"] = browsers_path
-
 
 def login(
     playwright: Playwright,