fix(crawl): throttle concurrent CrawlJobs and relax fpw/proxyscrape HTTP

- CrawlJob waits on crawl_slot before JobExecutor semaphore so crawl-all does not fill slots while queued
- BaseHTTPPlugin: longer connect budget for slow international links
- proxyscrape: jsDelivr mirror + longer GitHub/API phases
- fpw_*: higher timeouts/retries; lower internal concurrency on heavy multi-URL plugins

Made-with: Cursor

app/plugins/fpw_socks_ssl_proxy.py

@@ -14,7 +14,7 @@ class FpwSocksSslProxyPlugin(BaseHTTPPlugin):
 
     def __init__(self):
         super().__init__()
-        self.max_concurrency = 6
+        self.max_concurrency = 4
         # 与 sslproxies 同模板的镜像站较多，socks-proxy 在部分网络下不稳定，多源提高成功率
         self.urls = [
             "https://www.sslproxies.org/",
@@ -39,7 +39,7 @@ class FpwSocksSslProxyPlugin(BaseHTTPPlugin):
 
     async def crawl(self) -> List[ProxyRaw]:
         results: List[ProxyRaw] = []
-        htmls = await self.fetch_all(self.urls, timeout=12, retries=1)
+        htmls = await self.fetch_all(self.urls, timeout=25, retries=2)
         for url, html in zip(self.urls, htmls):
             if not html:
                 continue