feat: Yahoo Finance SSH proxy + Xiaomi MiMo LLM support

- Add SSH proxy via foreign server for Yahoo Finance bypass
- Add fallback in load_ohlcv and get_YFin_data_online
- Add LLM JSON decode retry (3 attempts) in NormalizedChatOpenAI
- Add yahoo_proxy.py utility module
- Add test_smoke.py and patches/

tradingagents/dataflows/yahoo_proxy.py

@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+"""Yahoo Finance proxy via foreign server.
+
+Routes yfinance requests through the foreign server to bypass local IP rate limiting.
+"""
+import subprocess
+import json
+import os
+import sys
+
+def _get_ssh_config():
+    """Load SSH credentials from vault."""
+    result = subprocess.run(
+        ["bash", "-c", 'source <(bash /root/.openclaw/workspace/scripts/vault.sh decrypt /root/.openclaw/workspace/secrets/credentials.env.enc) && echo "$FOREIGN_HOST $FOREIGN_PORT $FOREIGN_PASS"'],
+        capture_output=True, text=True, timeout=10
+    )
+    parts = result.stdout.strip().split()
+    if len(parts) != 3:
+        raise RuntimeError(f"Failed to load SSH config: {result.stderr}")
+    return parts[0], int(parts[1]), parts[2]
+
+def fetch_yahoo_via_ssh(url: str, timeout: int = 30) -> str:
+    """Fetch a Yahoo Finance URL through the foreign server via SSH."""
+    host, port, password = _get_ssh_config()
+    cmd = [
+        "sshpass", "-p", password,
+        "ssh", "-o", "StrictHostKeyChecking=no",
+        "-o", f"ConnectTimeout=15",
+        "-p", str(port), f"root@{host}",
+        f'curl -s "{url}" -H "User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36"'
+    ]
+    result = subprocess.run(cmd, capture_output=True, text=True, timeout=timeout)
+    if result.returncode != 0:
+        raise RuntimeError(f"SSH fetch failed: {result.stderr}")
+    return result.stdout
+
+def test_connection() -> bool:
+    """Test if Yahoo Finance is accessible via foreign server."""
+    try:
+        data = fetch_yahoo_via_ssh(
+            "https://query2.finance.yahoo.com/v8/finance/chart/AAPL?interval=1d&range=5d"
+        )
+        parsed = json.loads(data)
+        return "chart" in parsed and "result" in parsed.get("chart", {})
+    except Exception as e:
+        print(f"Connection test failed: {e}", file=sys.stderr)
+        return False
+
+if __name__ == "__main__":
+    if test_connection():
+        print("✅ Yahoo Finance proxy via foreign server: OK")
+    else:
+        print("❌ Yahoo Finance proxy via foreign server: FAILED")