[Task]: Add device selector

[ActiveChooN]

Description

Add a device selector to the application that allows users to choose the inference accelerator at the project level. The selected device is persisted as project configuration via the backend API.
Depends on #836

Component

UI (React frontend)

Acceptance Criteria

• A Device Picker is rendered in the toolbar
• Available devices are fetched from GET /system/devices and shown with names
• An Auto option is always present and is the default
• The currently selected device reflects the value stored on the project (from useCurrentProject)
• Selecting a new device calls PUT /projects/{id} with { device } and invalidates the project query

Implementation Notes

No response

Parent Epic

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Dependencies

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