fix: resolve curl_cffi TLS errors and fix FRED/upgrades endpoints

- Pin curl_cffi==0.7.4 to avoid BoringSSL bug in 0.12-0.14
- Patch curl_cffi Session to use safari TLS fingerprint instead of
  chrome, which triggers SSL_ERROR_SYSCALL on some networks
- Register FRED API key with OpenBB credentials at startup
- Fix macro overview to return latest data instead of oldest, and
  extract values by FRED series ID key
- Replace Finnhub upgrades endpoint (premium-only) with yfinance
  upgrades_downgrades which includes price target changes
- Remove redundant curl_cffi upgrade from Dockerfile

macro_service.py

@@ -36,19 +36,31 @@ def _to_dicts(result: Any) -> list[dict[str, Any]]:
     return [vars(result.results)]
 
 
-async def get_series(series_id: str, limit: int = 10) -> list[dict[str, Any]]:
+async def get_series(
+    series_id: str, limit: int = 10, latest: bool = False,
+) -> list[dict[str, Any]]:
     """Get a FRED time series by ID."""
     try:
+        fetch_limit = limit if not latest else None
+        kwargs: dict[str, Any] = {
+            "symbol": series_id,
+            "provider": PROVIDER,
+        }
+        if fetch_limit is not None:
+            kwargs["limit"] = fetch_limit
         result = await asyncio.to_thread(
             obb.economy.fred_series,
-            symbol=series_id,
-            limit=limit,
-            provider=PROVIDER,
+            **kwargs,
         )
         items = _to_dicts(result)
-        for item in items:
-            if "date" in item and not isinstance(item["date"], str):
-                item = {**item, "date": str(item["date"])}
+        items = [
+            {**item, "date": str(item["date"])}
+            if "date" in item and not isinstance(item["date"], str)
+            else item
+            for item in items
+        ]
+        if latest:
+            items = items[-limit:]
         return items
     except Exception:
         logger.warning("Failed to fetch FRED series %s", series_id, exc_info=True)
@@ -58,20 +70,22 @@ async def get_series(series_id: str, limit: int = 10) -> list[dict[str, Any]]:
 async def get_macro_overview() -> dict[str, Any]:
     """Get a summary of key macro indicators."""
     tasks = {
-        name: get_series(series_id, limit=1)
+        name: get_series(series_id, limit=1, latest=True)
         for name, series_id in SERIES.items()
     }
     results = await asyncio.gather(*tasks.values(), return_exceptions=True)
 
     overview: dict[str, Any] = {}
-    for name, result in zip(tasks.keys(), results):
+    for (name, series_id), result in zip(SERIES.items(), results):
         if isinstance(result, BaseException):
             logger.warning("Failed to fetch %s: %s", name, result)
             overview[name] = None
         elif result and len(result) > 0:
-            entry = result[0]
+            entry = result[-1]
+            # FRED returns values keyed by series ID, not "value"
+            value = entry.get(series_id) or entry.get("value")
             overview[name] = {
-                "value": entry.get("value"),
+                "value": value,
                 "date": str(entry.get("date", "")),
             }
         else: