feat: add pydantic schemas and state definitions

app/schemas.py

@@ -0,0 +1,18 @@
+from pydantic import BaseModel
+
+
+class HPI(BaseModel):
+    onset: str
+    location: str
+    duration: str
+    character: str
+    severity: str
+    aggravating: str
+    relieving: str
+
+
+class ClinicalBrief(BaseModel):
+    chief_complaint: str
+    hpi: HPI
+    ros: dict[str, list[str]]
+    generated_at: str

app/state.py

@@ -0,0 +1 @@
+# State is now defined in graph.py as part of LangGraph integration