closes #141580

Adds custom error messages when we miss any of the columns that FUSE requires.
We need a custom error message, because for a query like:

FROM wikipedia
| FORK (WHERE title:"Europe")
       (WHERE content:"Europe")
| FUSE

we simply return back a validation error:

line 5:3: Unknown column [_id]
line 5:3: Unknown column [_index]
line 5:3: Unknown column [_score]

it is not immediately apparent that these are the column FUSE needs, since _id, _index and _score are not even referenced in the query.