DM-16828: Add Job viewer to lsst.verify

[kfindeisen]

This PR adds the inspect_job.py script for getting a quick and uncluttered summary of a persisted job. User documentation has been added to the Sphinx build.

[parejkoj]

This looks handy, thanks for writing it.

My primary concern is preventing bitrot on this: is there a way to write a simple test of it with a sample job output? You could either lift the "working code" out into lsst.verify.something or maybe just run this as an executable from a test via subprocess.run().

[parejkoj]

Maybe better off putting this logic in main() and using ArgumentParser to manage the argv stuff.

[kfindeisen]

ArgumentParser seems kind of overkill here, don't you think? It's not a proper CLI, just a list of files.

[parejkoj]

Either way. I find using argparse to even handle "just a list of files" to be more robust, but its your call.

[jonathansick]

About putting the core business code into the Python package itself, see https://github.com/lsst/verify/blob/master/python/lsst/verify/report.py for something similar.

Report has slightly different information content (it so far focusses on tabulating pass/fail status). But it shows how you might create a class that could either render plain text on the command line, or something like HTML in a notebook.

[kfindeisen]

Ok, I'll try to move everything into python/ and make it an object that could potentially have multiple representations. Though I'm not sure I can get to the second part before the break.

[kfindeisen]

On second thought, I think creating a display object may be best deferred to a separate ticket. Making a display class that's specific to Job feels way too specialized, but creating an abstract interface that is Report-like will be inflexible if we want to add a third (or is that fourth?) output mode.

So I think it would be better to just add a unit test, and solve the problem of multiple output formats later.

[parejkoj]

That seems like a good approach.