Squashed 'common/' content from commit ff185b4

git-subtree-dir: common
git-subtree-split: ff185b42f0fa577446c3d00da3438dc148ee8102

artdag_common/middleware/__init__.py

@@ -0,0 +1,16 @@
+"""
+Middleware and FastAPI dependencies for Art-DAG servers.
+"""
+
+from .auth import UserContext, get_user_from_cookie, get_user_from_header, require_auth
+from .content_negotiation import wants_html, wants_json, ContentType
+
+__all__ = [
+    "UserContext",
+    "get_user_from_cookie",
+    "get_user_from_header",
+    "require_auth",
+    "wants_html",
+    "wants_json",
+    "ContentType",
+]