Add description to column properties, frontend impl.

[pavish]

Frontend aspect of #3069

Also fixes #3218

Technical details

• Adds description textarea to Column Properties section in Table Inspector.

Checklist

• My pull request has a descriptive title (not a vague title like Update index.md).
• My pull request targets the develop branch of the repository
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• My code follows the established code style of the repository.
• I added tests for the changes I made (if applicable).
• I added or updated documentation (if applicable).
• I tried running the project locally and verified that there are no
  visible errors.

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[seancolsen]

Looks good. Nice work, @pavish!