Initial commit of integrated agent system

backend/runtime/session.py

@@ -0,0 +1,14 @@
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class TradingSessionKey:
+    date: str
+    ticker: str | None = None
+
+    def __post_init__(self):
+        if not self.date:
+            raise ValueError("Session must have a date")
+
+    def key(self) -> str:
+        return f"{self.date}:{self.ticker or 'all'}"