feat(s2a_service): Add pure API authorization mode without browser

- Add S2A_API_MODE configuration option to enable browser-less authorization
- Implement S2AApiAuthorizer class using curl_cffi for browser fingerprint simulation
- Add Sentinel PoW (Proof of Work) solver with FNV-1a hashing algorithm
- Implement OAuth flow via direct API calls instead of browser automation
- Add s2a_api_authorize() function to handle email/password authentication
- Support proxy configuration for API requests
- Add requirements token generation for API authentication
- Update browser_automation.py to check S2A_API_MODE and route to API or browser flow
- Update config.py to load S2A_API_MODE from configuration
- Add api_mode option to config.toml.example with documentation
- Improves performance and stability by eliminating browser overhead while maintaining compatibility with existing browser-based flow

config.py

@@ -312,7 +312,7 @@ def reload_config() -> dict:
     global GPTMAIL_API_KEYS, GPTMAIL_DOMAINS, GPTMAIL_PREFIX
     global PROXY_ENABLED, PROXIES
     global S2A_API_BASE, S2A_ADMIN_KEY, S2A_ADMIN_TOKEN
-    global S2A_CONCURRENCY, S2A_PRIORITY, S2A_GROUP_NAMES, S2A_GROUP_IDS
+    global S2A_CONCURRENCY, S2A_PRIORITY, S2A_GROUP_NAMES, S2A_GROUP_IDS, S2A_API_MODE
     global CONCURRENT_ENABLED, CONCURRENT_WORKERS
 
     result = {
@@ -387,6 +387,7 @@ def reload_config() -> dict:
             S2A_PRIORITY = _s2a.get("priority", 50)
             S2A_GROUP_NAMES = _s2a.get("group_names", [])
             S2A_GROUP_IDS = _s2a.get("group_ids", [])
+            S2A_API_MODE = _s2a.get("api_mode", False)
 
     except Exception as e:
         errors.append(f"config.toml: {e}")
@@ -619,6 +620,7 @@ S2A_CONCURRENCY = _s2a.get("concurrency", 10)
 S2A_PRIORITY = _s2a.get("priority", 50)
 S2A_GROUP_NAMES = _s2a.get("group_names", [])
 S2A_GROUP_IDS = _s2a.get("group_ids", [])
+S2A_API_MODE = _s2a.get("api_mode", False)  # 是否使用纯 API 授权模式 (无需浏览器)
 
 # 账号
 _account = _cfg.get("account", {})