4987 - support `browse_trace` tool in SubX

I've extracted it into a separate binary, independent of my Mu prototype.

I also cleaned up my tracing layer to be a little nicer. Major improvements:

- Realized that incremental tracing really ought to be the default.
  And to minimize printing traces to screen.

- Finally figured out how to combine layers and call stack frames in a
  single dimension of depth. The answer: optimize for the experience of
  `browse_trace`. Instructions occupy a range of depths based on their call
  stack frame, and minor details of an instruction lie one level deeper
  in each case.

Other than that, I spent some time adjusting levels everywhere to make
`browse_trace` useful.

1 files changed, 1 insertions, 1 deletions

diff --git a/055shape_shifting_container.cc b/055shape_shifting_container.cc
index c3d0246f..1fb5f176 100644
--- a/055shape_shifting_container.cc
+++ b/055shape_shifting_container.cc
@@ -132,7 +132,7 @@ if (!info.type_ingredient_names.empty()) continue;
 
 :(before "End container Name Refinements")
 if (name.find(':') != string::npos) {
-  trace("parse") << "container has type ingredients; parsing" << end();
+  trace(101, "parse") << "container has type ingredients; parsing" << end();
   if (!read_type_ingredients(name, command)) {
     // error; skip rest of the container definition and continue
     slurp_balanced_bracket(in);