repl: Handle user-defined res definitions

[dwijnand]

No description provided.

[SethTisue]

@dwijnand looks like the pattern handling only works because we special-cased tuples:

scala> val Some((res0, res1)) = Option((1, "foo"))
val res0: Int = 1
val res1: String = foo
                                                                                                                        
scala> res0
-- [E045] Cyclic Error: --------------------------------------------------------
1 |res0
  |^
  |Recursive value res0 needs type

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1 error found