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TMSU
TMSU lets you tags your files and then access them through a nifty virtual filesystem from any other application.
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SurveyJS
Open-Source JSON Form Builder to Create Dynamic Forms Right in Your App. With SurveyJS form UI libraries, you can build and style forms in a fully-integrated drag & drop form builder, render them in your JS app, and store form submission data in any backend, inc. PHP, ASP.NET Core, and Node.js.
TagSpaces - GUI, and a little different than TMSU. It displays all of your tagged files and lets you sort through them. It uses a different approach for tagging than TMSU, so I'd recommend trying both and seeing which you like best.. (https://www.tagspaces.org)
TMSU (what some others suggested here) has a feature request for adding support for it...but not implemented yet it seems.