Docs : Add heatmap visualization topic (#24456)
Docs : Add heatmap visualization topic (#24456)

* Create heatmap.md

* Update heatmap.md

* Docs: add missing heatmap fields description.

* Update heatmap.md

Co-authored-by: Alexander Zobnin <72f2cce48f76fba77af75851c46b74b28764a85a@gmail.com>
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