Add variation support & extend term description block

[sarthaknagoshe2002]

What?

Part of #49094
Improvisation for this PR

1. Modify the term description block to render the preview ✅
2. Update the term description to render description on the frontend when inside the term query block ✅
3. Add variation picker ✅
4. Add multiple variations ✅ ( 4 variations added, will add more if needed )

Why?

1. To include the term description block in the term-query eco system.
2. Have multiple variation of the term template.

Testing Instructions

Note: Paused the development of pagination feature until #70720 looks complete and consists of all the blocks required in the term query block's eco system

[github-actions]

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[github-actions]

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