add dxt install capability

core/context.py

@@ -0,0 +1,22 @@
+# core/context.py
+import contextvars
+from typing import Optional
+
+# Context variable to hold injected credentials for the life of a single request.
+_injected_oauth_credentials = contextvars.ContextVar(
+    "injected_oauth_credentials", default=None
+)
+
+def get_injected_oauth_credentials():
+    """
+    Retrieve injected OAuth credentials for the current request context.
+    This is called by the authentication layer to check for request-scoped credentials.
+    """
+    return _injected_oauth_credentials.get()
+
+def set_injected_oauth_credentials(credentials: Optional[dict]):
+    """
+    Set or clear the injected OAuth credentials for the current request context.
+    This is called by the service decorator.
+    """
+    _injected_oauth_credentials.set(credentials)