feat: 全面SSH中转代理 + mimo-v2.5-pro支持

- Yahoo Finance: 跳过本地限流，直接走SSH中转
- StockTwits: 直连403时自动fallback到SSH中转
- Reddit: 网络不可达时自动fallback到SSH中转
- Polymarket: 网络不可达时自动fallback到SSH中转
- FRED: 配置API Key (825283926dd016ea66e96cc919e047da)
- .env: 新增FRED_API_KEY和OPENAI_COMPATIBLE_API_KEY
- test_xiaomi.py: 小米mimo-v2.5-pro测试脚本

tradingagents/dataflows/reddit.py

@@ -31,6 +31,7 @@ from urllib.parse import urlencode
 from urllib.request import Request, urlopen
 
 from .symbol_utils import crypto_base
+from .stockstats_utils import _fetch_via_ssh
 
 logger = logging.getLogger(__name__)
 
@@ -123,8 +124,13 @@ def _fetch_subreddit_rss(
     except (OSError, http.client.HTTPException, ET.ParseError) as exc:
         # OSError covers URLError/TimeoutError/connection resets; HTTPException
         # covers chunked-transfer errors (IncompleteRead/BadStatusLine, #1024).
-        logger.warning("Reddit RSS fetch failed for r/%s · %s: %s", sub, ticker, exc)
-        return []
+        logger.warning("Reddit RSS direct fetch failed for r/%s · %s: %s, trying SSH proxy...", sub, ticker, exc)
+        try:
+            proxy_data = _fetch_via_ssh(url, timeout=timeout)
+            root = ET.fromstring(proxy_data.encode() if isinstance(proxy_data, str) else proxy_data)
+        except Exception as proxy_exc:
+            logger.warning("Reddit RSS proxy also failed for r/%s · %s: %s", sub, ticker, proxy_exc)
+            return []
 
     posts = []
     for entry in root.findall("atom:entry", _ATOM_NS)[:limit]: