Fleet Management grid sample implementation

[dkamburov]

Implement a Fleet Management grid sample matching the design from Fleet Management sample in webcomponents.

Design reference:

• Master-detail grid focused on managing vehicle acquisition, operations, and maintenance records.
• Nested detail panels or child grids for vehicle history, maintenance logs, and assignment.
• Core features: expandable master rows, summary cells, CRUD operations, filters, and search.
• Modern visual style following Material/Dark theme.
• Sample Design (WebComponents)

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• Theme: Material
• Mode: Dark
• See also WebComponents repo for base implementation.