security: harden connector policy and add dashboard widget

src/govoplan_files/backend/storage/http_client.py

@@ -185,15 +185,23 @@ class _OutboundPolicyHTTPTransport(httpx.BaseTransport):
         self._connection_pool.close()
 
 
+_CONNECTOR_HTTP_CLIENT = httpx.Client(
+    transport=_OutboundPolicyHTTPTransport(),
+    follow_redirects=False,
+    timeout=15.0,
+)
+
+
 @contextmanager
 def _stream_connector_request(method: str, url: str, **kwargs: Any) -> Iterator[httpx.Response]:
-    with httpx.Client(
-        transport=_OutboundPolicyHTTPTransport(),
-        follow_redirects=False,
-        timeout=kwargs.pop("timeout", 15.0),
-    ) as client:
-        with client.stream(method, url, **kwargs) as response:
-            yield response
+    timeout = kwargs.pop("timeout", 15.0)
+    with _CONNECTOR_HTTP_CLIENT.stream(
+        method,
+        url,
+        timeout=timeout,
+        **kwargs,
+    ) as response:
+        yield response
 
 
 def request_connector_bytes(