fix: use ssl.create_default_context for the TLS server

SonarCloud python:S4423 wants the stdlib helper instead of a bare
SSLContext(PROTOCOL_TLS_SERVER); create_default_context selects the
hardened cipher suite list, disables compression, and locks in
TLS 1.2 minimum (we keep the explicit minimum_version pin as a
belt-and-braces check).

Author: JE-Chen

je_load_density/utils/socket_server/load_density_socket_server.py

@@ -50,9 +50,11 @@ def __init__(
         self.server: socket.socket = socket.socket(AF_INET, SOCK_STREAM)
         self._tls_context: Optional[ssl.SSLContext] = None
         if certfile and keyfile:
-            self._tls_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
-            # Pin minimum TLS version so older insecure suites cannot be
-            # negotiated; PROTOCOL_TLS_SERVER alone permits TLS 1.0/1.1.
+            # create_default_context picks Python's hardened TLS defaults
+            # (TLS 1.2+ minimum, restricted ciphers, no compression). We
+            # pin minimum_version explicitly as belt-and-braces in case
+            # the default ever loosens on an older interpreter.
+            self._tls_context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
             self._tls_context.minimum_version = ssl.TLSVersion.TLSv1_2
             self._tls_context.load_cert_chain(certfile=certfile, keyfile=keyfile)