add sandbox extra env config

adapter/config/loader.py

@@ -324,9 +324,24 @@ def _load_sandbox_config(
             env,
             'APP_SANDBOX_VOLUME_MOUNT_PATH',
         ),
+        extra_env=_load_sandbox_extra_env(section),
     )
 
 
+def _load_sandbox_extra_env(section: Mapping[str, object]) -> dict[str, str]:
+    raw = section.get('env')
+    if raw is None:
+        return {}
+    if not isinstance(raw, dict):
+        raise ConfigError('invalid sandbox.env')
+    result: dict[str, str] = {}
+    for key, value in raw.items():
+        if not isinstance(key, str):
+            raise ConfigError('invalid sandbox.env key')
+        result[key] = str(value)
+    return result
+
+
 def _load_otel_config(
     data: Mapping[str, object],
     env: Mapping[str, str],