feat: Implement currency management with models, routes, and UI updates; add backfill script for existing records

routes/currencies.py

@@ -0,0 +1,17 @@
+from typing import List, Dict, Any
+
+from fastapi import APIRouter, Depends
+from sqlalchemy.orm import Session
+
+from models.currency import Currency
+from routes.dependencies import get_db
+
+router = APIRouter(prefix="/api/currencies", tags=["Currencies"])
+
+
+@router.get("/", response_model=List[Dict[str, Any]])
+def list_currencies(db: Session = Depends(get_db)):
+    results = []
+    for c in db.query(Currency).filter_by(is_active=True).order_by(Currency.code).all():
+        results.append({"id": c.code, "name": f"{c.name} ({c.code})", "symbol": c.symbol})
+    return results