fix: extend make_async_client to proxy provider and IP pool

Migrate remaining httpx.AsyncClient call sites in proxy/ package to
use make_async_client(), completing the DISABLE_SSL_VERIFY coverage
across all outbound HTTP requests in the project.

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

proxy/providers/wandou_http_proxy.py

@@ -30,6 +30,7 @@ import httpx
 from proxy import IpCache, IpGetError, ProxyProvider
 from proxy.types import IpInfoModel
 from tools import utils
+from tools.httpx_util import make_async_client
 
 
 class WanDouHttpProxy(ProxyProvider):
@@ -65,7 +66,7 @@ class WanDouHttpProxy(ProxyProvider):
         need_get_count = num - len(ip_cache_list)
         self.params.update({"num": min(need_get_count, 100)})  # Maximum 100
         ip_infos = []
-        async with httpx.AsyncClient() as client:
+        async with make_async_client() as client:
             url = self.api_path + "?" + urlencode(self.params)
             utils.logger.info(f"[WanDouHttpProxy.get_proxy] get ip proxy url:{url}")
             response = await client.get(