Add column descriptions to DynamicTable HTML representation

[h-mayorquin]

Previously, there was no way to view column descriptions in the HTML display of DynamicTables. I think this will be useful to add. When working on conversion projects I use the HTML to check that everthing is as intended. In addition, this feature will be useful for people reading new NWBFiles through the notebok (e.g. from Dandi) as it improves the representation of common but important tables such as trials, electrodes, and units. This is especially important for custom-added columns, where most columns are hard to interpret without a description.

For the implementation, a new collapsible "columns" section is added to the generate_html_repr() method in DynamicTable. Each column is displayed as an individually collapsible item (collapsed by default) that shows the column's description when expanded. Column names include an access code tooltip (e.g., ['column_name']) that can be clicked to copy to clipboard, consistent with other field displays in the HTML representation.

This is how it looks:

Checklist

• Did you update CHANGELOG.md with your changes?
• Does the PR clearly describe the problem and the solution?
• Have you reviewed our Contributing Guide?
• Does the PR use "Fix #XXX" notation to tell GitHub to close the relevant issue numbered XXX when the PR is merged?

[codecov]

Codecov Report

❌ Patch coverage is 86.66667% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.44%. Comparing base (a06614b) to head (e7a7aa4).
⚠️ Report is 1 commits behind head on dev.

Files with missing lines	Patch %	Lines
src/hdmf/common/table.py	86.66%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #1369      +/-   ##
==========================================
- Coverage   92.44%   92.44%   -0.01%     
==========================================
  Files          42       42              
  Lines        9747     9762      +15     
  Branches     1979     1982       +3     
==========================================
+ Hits         9011     9024      +13     
- Misses        462      463       +1     
- Partials      274      275       +1     

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[rly]

Great idea. Thanks @h-mayorquin !