Add API to rename subsets

[rosteen]

Started from #1291 and #2610, I think I've covered all the points raised in #1539 but I'm still doing a bit more work, so opening as draft.

[rosteen]

A couple thoughts as I move this to Ready for Review:

1. I had initially put _rename_subsets in app.py because I thought that it would touch a lot of things throughout the app, but now those are pretty much handled by broadcasting SubsetRenameMessage. Would it be better to move this to subset_tools.py at this point?

2. _check_valid_subset_label is currently only set up to Warn, but I coded the warn_if_invalid kwarg as a toggle so that it could potentially return the warning string instead, for live updating a displayed warning in the UI as the label is typed. I wasn't sure if that should be part of this ticket or the UI one.

3. I started down the path of making the label check case-insensitive, but it seemed like that was going to end up being more confusing for the user, so it's currently case sensitive.

[codecov]

Codecov Report

Attention: Patch coverage is 58.82353% with 42 lines in your changes missing coverage. Please review.

Project coverage is 87.96%. Comparing base (24c4440) to head (4c431a9).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
jdaviz/core/template_mixin.py	33.33%	16 Missing ⚠️
jdaviz/app.py	64.28%	15 Missing ⚠️
jdaviz/core/events.py	53.33%	7 Missing ⚠️
...nfigs/default/plugins/subset_tools/subset_tools.py	80.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3356      +/-   ##
==========================================
- Coverage   88.12%   87.96%   -0.16%     
==========================================
  Files         127      127              
  Lines       19574    19667      +93     
==========================================
+ Hits        17249    17301      +52     
- Misses       2325     2366      +41     

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[kecnry]

Noticed a few things (some could be deferred to follow-ups):

• trying to rename a subset that does not exist raises a cryptic error message, it would be nice to catch this immediately and raise a useful message
• renamed subsets (I renamed 'Subset 1' to 'Subset blah') no longer appear in the new data-menu/legend or in plot options
• I think an invalid rename should raise an actual error (at least when triggered from the API - we might want to catch those eventually from the UI and display a message instead of a traceback)
• renaming something to Subset N can eventually conflict with the default subset created by glue
• this currently allows naming the subset the same as an existing data-label (and do we need to add checks for loading data that they cannot match any existing subset name either) (ok, it actually didn't, it just raised a warning instead of error - see above)
• renaming a subset results in duplicate entries in the export plugin
• update entries in data.meta['_update_live_plugin_results'] so that the live-connections remain intact

[javerbukh]

To add to @kecnry's points, I see the old subset name in Line Analysis under Data. That may be because the data was created with Subset 1, but I'm not sure if we keep the name in that case or go through data created with the old name and update that too. That may be a huge headache though so that can be a follow up effort.

[rosteen]

To add to @kecnry's points, I see the old subset name in Line Analysis under Data. That may be because the data was created with Subset 1, but I'm not sure if we keep the name in that case or go through data created with the old name and update that too. That may be a huge headache though so that can be a follow up effort.

I was planning to leave data entries created with the old subset name as-is, at least for now. I can add some documentation that that's the case (or we can add that once the UI part of this is done). It might not end up being that bad to implement, but I was worried about potential complexities (for example, if doing a simple find replace in the labels of the data objects, what if you're renaming "Subset 1" but there's also a "Subset 10"?).

[kecnry]

There is an issue though where the automatic updating spectrum returns when the old spectrum is updated, resulting in duplicated entries. Maybe we can defer the renaming of data-entries, but still update entries in data.meta['_update_live_plugin_results'] so that the live-connections remain intact?

[kecnry]

Is this more performant or just a shortcut (in which case I'm not sure if its worth the extra code and test-coverage or not, but don't have a strong opinion)?

Just a note to future selves: eventually we likely will want to migrate this logic into the subset dropdown itself (so these would become subset_tools.subset.rename...) since we're planning to use an editable select component, but I think it still makes sense to expose methods at the top-level in this plugin for convenience, so we can always just move the logic there and then have these methods call that instead.

[javerbukh]

Besides the points @kecnry brought up and the remaining print statement, this looks good!