refactoring: TypeScript migration, security fixes,

client/src/hooks/usePlaceSelection.ts

@@ -0,0 +1,18 @@
+import { useState, useCallback } from 'react'
+
+export function usePlaceSelection() {
+  const [selectedPlaceId, _setSelectedPlaceId] = useState<number | null>(null)
+  const [selectedAssignmentId, setSelectedAssignmentId] = useState<number | null>(null)
+
+  const setSelectedPlaceId = useCallback((placeId: number | null) => {
+    _setSelectedPlaceId(placeId)
+    setSelectedAssignmentId(null)
+  }, [])
+
+  const selectAssignment = useCallback((assignmentId: number | null, placeId: number | null) => {
+    setSelectedAssignmentId(assignmentId)
+    _setSelectedPlaceId(placeId)
+  }, [])
+
+  return { selectedPlaceId, selectedAssignmentId, setSelectedPlaceId, selectAssignment }
+}