[frontend] - Add customizable UI layout system

[Hydrax117]

Location: frontend/src/components/layout/

Users can't customize dashboard layout.

Acceptance Criteria:

• Drag-and-drop widget reordering
• Add/remove widgets
• Resize widgets
• Save layout per user
• Presets for different roles

[veemakama]

@veemakama has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi Maintainer, I would love to work on this issue. please assign

ℹ️ Repo Maintainers: To accept this application, review their application or assign @veemakama to this issue.