Retrieves the most recent JoinReport object from any *_join_spy() call.
Useful when using .quiet = TRUE in pipelines and wanting to inspect
the diagnostics afterward.
Examples
orders <- data.frame(id = 1:3, value = c(10, 20, 30))
customers <- data.frame(id = c(1, 2, 4), name = c("A", "B", "D"))
# Silent join in a pipeline
result <- left_join_spy(orders, customers, by = "id", .quiet = TRUE)
# Inspect the report afterward
last_report()