convert all eval visualization paths to incrementally building expression trees, rather than using final eval bundles; ensure all evaluation paths, in various circumstances (single line viz, row viz), go through exactly the same path; deduplicate single-row-expr evaluation paths

src/eval/eval_bundles.h

@@ -13,15 +13,16 @@ struct E_Eval
   E_Value value;
   E_Mode mode;
   E_Space space;
+  E_Expr *expr;
   E_TypeKey type_key;
   E_InterpretationCode code;
   E_MsgList msgs;
-  U64 advance;
 };
 
 ////////////////////////////////
 //~ rjf: Bundled Evaluation Functions
 
+internal E_Eval e_eval_from_expr(Arena *arena, E_Expr *expr);
 internal E_Eval e_eval_from_string(Arena *arena, String8 string);
 internal E_Eval e_autoresolved_eval_from_eval(E_Eval eval);
 internal E_Eval e_dynamically_typed_eval_from_eval(E_Eval eval);