Challenge 1: Resolving haskell2-2's Own Challenge 3 Scenario for Real — Possible Solution
====================================================================

Main.hs:

findUser :: Int -> Maybe String
findUser 5 = Just "alice@example.com"
findUser _ = Nothing

findOrderByEmail :: String -> Maybe String
findOrderByEmail "alice@example.com" = Just "Order #42"
findOrderByEmail _ = Nothing

findRecentOrder :: Int -> Maybe String
findRecentOrder userId = findUser userId >>= \email -> findOrderByEmail email

main :: IO ()
main = do
  print (findRecentOrder 5)   -- successful chain
  print (findRecentOrder 99)  -- fails at the first step

Output:

    Just "Order #42"
    Nothing

Explanation:
findRecentOrder 5 first calls findUser 5, which succeeds with
Just "alice@example.com". >>= unwraps that real email string and
passes it to the lambda, which calls findOrderByEmail with the actual
value -- exactly the dependency haskell2-2's own Applicative example
couldn't express. findRecentOrder 99 fails at the very first step:
findUser 99 is Nothing, so >>= short-circuits immediately, never even
calling the lambda or reaching findOrderByEmail at all.

WHY THIS WORKS AS AN ANSWER
------------------------------
This implements the exact user-lookup-then-email-lookup chain the
chapter names as resolving haskell2-2's own unresolved example,
demonstrating both the successful dependent chain and the short-
circuit-on-failure case.