fix: 修复爬虫网络层、验证队列卡死及 API 500 错误

- 修复 BaseHTTPPlugin 连接池、并发控制、异常日志、超时策略
- 修复/增强 8 个爬虫插件的稳定性和 fallback 机制
- 清理 validation_tasks 表 4 万+ pending 任务，避免队列卡死
- 修复 app/api/main.py 缺失全局 app 实例导致的 500 错误
- 提升前端 Axios 超时到 120 秒，避免请求断开
- 修复插件统计持久化和调度器生命周期问题

app/plugins/proxylist_download.py

@@ -8,48 +8,87 @@ class ProxyListDownloadPlugin(BaseHTTPPlugin):
     default_config = {"max_pages": 5}
     name = "proxylist_download"
     display_name = "ProxyListDownload"
-    description = "从 ProxyListDownload API 获取代理"
+    description = "从 GitHub 公开代理列表获取代理"
 
     def __init__(self):
         super().__init__()
-        self.urls = [
-            "https://www.proxy-list.download/api/v1/get?type=http",
-            "https://www.proxy-list.download/api/v1/get?type=https",
-            "https://www.proxy-list.download/api/v1/get?type=socks4",
-            "https://www.proxy-list.download/api/v1/get?type=socks5",
+        # 首选 GitHub raw + fallback 备用源（jsdelivr CDN 或 ProxyScrape API）
+        self.sources = [
+            {
+                "primary": "https://raw.githubusercontent.com/komutan234/Proxy-List-Free/main/proxies/http.txt",
+                "fallbacks": [
+                    "https://cdn.jsdelivr.net/gh/komutan234/Proxy-List-Free@main/proxies/http.txt",
+                    "https://api.proxyscrape.com/v2/?request=get&protocol=http&timeout=10000&country=all&ssl=all&anonymity=all",
+                ],
+                "protocol": "http",
+            },
+            {
+                "primary": "https://raw.githubusercontent.com/komutan234/Proxy-List-Free/main/proxies/socks4.txt",
+                "fallbacks": [
+                    "https://cdn.jsdelivr.net/gh/komutan234/Proxy-List-Free@main/proxies/socks4.txt",
+                    "https://api.proxyscrape.com/v2/?request=get&protocol=socks4&timeout=10000&country=all",
+                ],
+                "protocol": "socks4",
+            },
+            {
+                "primary": "https://raw.githubusercontent.com/komutan234/Proxy-List-Free/main/proxies/socks5.txt",
+                "fallbacks": [
+                    "https://cdn.jsdelivr.net/gh/komutan234/Proxy-List-Free@main/proxies/socks5.txt",
+                    "https://api.proxyscrape.com/v2/?request=get&protocol=socks5&timeout=10000&country=all",
+                ],
+                "protocol": "socks5",
+            },
         ]
 
+    def _detect_protocol(self, url: str) -> str:
+        """根据 URL 判断协议（注意不要用 https:// 来判断）"""
+        if "socks4" in url:
+            return "socks4"
+        elif "socks5" in url:
+            return "socks5"
+        elif "/http.txt" in url or "protocol=http" in url:
+            return "http"
+        return "http"
+
+    def _parse_lines(self, html: str, protocol: str) -> List[ProxyRaw]:
+        """解析代理文本，统一处理 \r\n、\n 两种换行以及可能存在的空行"""
+        results = []
+        # 统一替换为 \n 后再分割
+        text = html.replace("\r\n", "\n").replace("\r", "\n")
+        for line in text.split("\n"):
+            line = line.strip()
+            if not line or ":" not in line:
+                continue
+            parts = line.split(":")
+            if len(parts) >= 2:
+                ip = parts[0].strip()
+                port = parts[1].strip()
+                if ip and port.isdigit():
+                    results.append(ProxyRaw(ip, int(port), protocol))
+        return results
+
     async def crawl(self) -> List[ProxyRaw]:
         results = []
-        for url in self.urls:
-            html = await self.fetch(url, timeout=30)
-            if not html:
+        # 并发请求所有 primary URL
+        primary_urls = [s["primary"] for s in self.sources]
+        primary_htmls = await self.fetch_all(primary_urls, timeout=15)
+
+        for idx, html in enumerate(primary_htmls):
+            source = self.sources[idx]
+            protocol = source.get("protocol") or self._detect_protocol(source["primary"])
+
+            if html and html.strip():
+                results.extend(self._parse_lines(html, protocol))
                 continue
 
-            # 根据 URL 判断协议
-            if "type=socks4" in url:
-                protocol = "socks4"
-            elif "type=socks5" in url:
-                protocol = "socks5"
-            elif "type=https" in url:
-                protocol = "https"
-            else:
-                protocol = "http"
-
-            lines = html.split("\r\n")
-            if len(lines) <= 1:
-                lines = html.split("\n")
-
-            for line in lines:
-                line = line.strip()
-                if not line or ":" not in line:
-                    continue
-                parts = line.split(":")
-                if len(parts) >= 2:
-                    ip = parts[0].strip()
-                    port = parts[1].strip()
-                    if ip and port.isdigit():
-                        results.append(ProxyRaw(ip, int(port), protocol))
+            # primary 返回空或仅空白字符，依次尝试 fallback
+            logger.warning(f"{self.display_name} 主源返回空，尝试 fallback: {source['primary']}")
+            for fallback_url in source["fallbacks"]:
+                fallback_html = await self.fetch(fallback_url, timeout=15)
+                if fallback_html and fallback_html.strip():
+                    fb_protocol = source.get("protocol") or self._detect_protocol(fallback_url)
+                    results.extend(self._parse_lines(fallback_html, fb_protocol))
+                    break
 
         if results:
             logger.info(f"{self.display_name} 解析完成，获得 {len(results)} 个潜在代理")