GHCi: Reimplement +c using the same machinery as .hie files

See #16804

This reimplements GHCi :set +c with hie files.

The test case T16804 is marked as broken, as some types can't be deduced, which really should be. But maybe there are other strategies to get that type information.

For example

 % executing: ":type-at T16804a.hs 13 14 13 14 undefined"
 % file snippet:
 > testFunction :: Test -> Test -> Bool
 > testFunction A B = True
 %              ^
 > testFunction B A = True
 % output:
-undefined :: Test
+undefined :: undefined
 
 % executing: ":type-at T16804a.hs 13 16 13 16 undefined"
 % file snippet:
 > testFunction :: Test -> Test -> Bool
 > testFunction A B = True
 %                ^
 > testFunction B A = True
 % output:
-undefined :: Test
+undefined :: undefined

are changes to the test output, which demonstrate a quality reduction sadly.

Also function applications expressions don't carry type information in the hie file, so thats also a reduction of the quality.

But there are also quality improvements especially for :uses as shown by this change of the test output:

 % executing: ":uses T16804a.hs 13  1 13 12"
 % file snippet:
 > testFunction :: Test -> Test -> Bool
 > testFunction A B = True
 % ^~~~~~~~~~~^
 > testFunction B A = True
 % output:
+T16804a.hs:(12,1)-(12,12)
 T16804a.hs:(13,1)-(13,12)
-T16804a.hs:(13,1)-(13,12)
+T16804a.hs:(14,1)-(14,12)
+T16804a.hs:(15,1)-(15,12)
+T16804b.hs:(7,10)-(7,21)
+T16804c.hs:(9,18)-(9,29)
+T16804c.hs:(12,17)-(12,28)
+T16804c.hs:(15,17)-(15,28)

I am willing to invest more time and work into this, but would need some pointers as to which directions I should follow to improve on that.

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