WIP: Add Devices sidebar section for Dynamic Resource Allocation APIs

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Overview

Add a new "Devices" sidebar section in the Headlamp UI supporting four Kubernetes Dynamic Resource Allocation (DRA) resources from the resource.k8s.io/v1 API group (Kubernetes 1.34+):

Resource	Scope	API Name
DeviceClass	Cluster	deviceclasses
ResourceSlice	Cluster	resourceslices
ResourceClaim	Namespaced	resourceclaims
ResourceClaimTemplate	Namespaced	resourceclaimtemplates

This involves:

1. K8s resource classes — Create four new classes in frontend/src/lib/k8s/ (one per resource) extending KubeObject, and register them in ResourceClasses.
2. UI components — Create list and detail view components for each resource under frontend/src/components/device/ (8 components total).
3. Sidebar entry — Add a new "Devices" section in useSidebarItems.tsx with sub-items for each resource.
4. Routes — Register list and detail routes for all four resources in the router. Namespaced resources (ResourceClaim, ResourceClaimTemplate) use :namespace/:name paths; cluster-scoped resources (DeviceClass, ResourceSlice) use :name only.
5. i18n — Add translation keys for the new labels.