fish_trace filters to avoid suppressing traces from binds etc

[krobelus]

Today fish_trace=1 traces all fish script code except bind/events/prompt/title.
(Also fish_should_add_to_history which is part of bind).

Let's allow enabling these categories. This is mainly to help debugging; I'm
not sure how useful this is to people who are not very familiar with fish. I'd
only list this in the changelog once we have a better design (reject typos
like "fish_trace=binds" and maybe allow turning off the default script trace).

[faho]

Fixes #7781

[krobelus]

also set -lx fish_trace 1 should override any existing suppression I think, since this is a debuggin-only feature.

[faho]

also set -lx fish_trace 1 should override any existing suppression I think, since this is a debuggin-only feature.

You mean setting it to "1" should show all traces? I would rather have it stay as it is, because otherwise it's overly chatty.

How about an "all" option that turns on all traces instead?

(this is similar to FLOG, where we have a few categories that are just much too chatty)

[krobelus]

I was just talking about the problem that there is currently no way to "un-suppress" tracing.
I agree "1/on/true/script" should (as it does today) trace only normal commands.
Agreed with the "all" option (or * I guess), this patch already includes it.