dead code deletion, begin extending eval/eval-viz to work on expr-chains rather than single expressions; fixes / convergence for watch window

src/eval/eval_bundles.h

@@ -13,7 +13,7 @@ struct E_Eval
   E_Value value;
   E_Mode mode;
   E_Space space;
-  E_Expr *expr;
+  E_ExprChain exprs;
   E_TypeKey type_key;
   E_InterpretationCode code;
   E_MsgList msgs;
@@ -23,6 +23,7 @@ struct E_Eval
 //~ rjf: Bundled Evaluation Functions
 
 internal E_Eval e_eval_from_expr(Arena *arena, E_Expr *expr);
+internal E_Eval e_eval_from_exprs(Arena *arena, E_ExprChain exprs);
 internal E_Eval e_eval_from_string(Arena *arena, String8 string);
 internal E_Eval e_eval_from_stringf(Arena *arena, char *fmt, ...);
 internal E_Eval e_autoresolved_eval_from_eval(E_Eval eval);