init repo

app/middleware/base.py

@@ -0,0 +1,22 @@
+"""Middleware base class — before/after hooks around graph execution."""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+
+from app.graph.state import ReportState
+
+
+class Middleware(ABC):
+    """Base middleware. Subclasses override before() and/or after()."""
+
+    name: str = "base"
+    enabled: bool = True
+
+    async def before(self, state: ReportState) -> ReportState:
+        """Called before graph execution. Modify state as needed."""
+        return state
+
+    async def after(self, state: ReportState) -> ReportState:
+        """Called after graph execution. Modify state as needed."""
+        return state