feat(tvix/eval): use fancy error formatting in REPL

Change-Id: I8d5652d797b012bc3d5248ca2b2d0c87572dbf2e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6851
Tested-by: BuildkiteCI
Reviewed-by: wpcarro <wpcarro@gmail.com>

tvix/eval/src/main.rs

@@ -72,7 +72,7 @@ fn run_prompt(eval_options: tvix_eval::Options) {
                     Ok(result) => {
                         println!("=> {} :: {}", result, result.type_of());
                     }
-                    Err(err) => println!("{}", err),
+                    Err(_) => { /* interpret takes care of error formatting */ }
                 }
             }
             Err(ReadlineError::Interrupted) | Err(ReadlineError::Eof) => break,