Formatter improvements

[janmasrovira]

1. Closes Lambda functions miss the first pipe when formatted #3192. The first pipe is ensured in a multi-clause lambda.
2. Bugfix: Pragmas are now properly printed for deriving statements. Previously they were never printed.
3. Record types are always declared in a new line, even if they have a single constructor and fit in a line. I think this change improves readability.

   -- before
   type Eq A := mkEq@{builtin isEqual eq : A -> A -> Bool};
   
   -- after
   type Eq A :=
     mkEq@{
       builtin isEqual
       eq : A -> A -> Bool;
     };
   

4. I've formatted the stdlib (Format juvix-stdlib#150).
5. I've refactored some code related to adding the first pipe so that it is reused for cases, lambdas and types.
6. Now ConstructorDef has a proper PrettyCode instance and does not need to be passed a bool indicating whether it is the only constructor in a definition.