[Docs] feat : Add documentation for "Layers Panel" feature in kanvas

[kishore08-07]

Description:

This issue is to create dedicated documentation page for the "Layers Panel" feature in kanvas tool. This page should clearly explain how layers help users show, hide, and group objects on the same board, enabling cleaner diagrams and phased design visualization.

Layers Panel feature description:

“Use layers to show, hide, and group objects on the same board—perfect for building detailed diagrams or revealing project phases.”

Scope of Work:

• Explore the latest Layers Panel feature in the Canvas tool.
• Document its functionality and usage clearly.
• Include step-by-step explanations with:
  - Screenshots, GIFs/videos demonstrating the panel’s behaviors (creating layers, toggling visibility, grouping, etc.)
• Ensure the content is user-friendly and structured for the Canvas section of the docs.

Reference:
Use the existing content for context:
https://docs.layer5.io/kanvas/advanced/performance/#optimize-your-design-using-the-layers-panel

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Contributor Guide and Resources

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