Update Device Details UI to allow Edits

[mfreeman451]

Need to add the ability to edit Device Details from the Device Details page, maybe a simple 'Edit' button protected by RBAC (only admins, or groups given permission can edit), after you hit the edit, the device details page form fields become mutable.

Probably need to make sure we're using phx-debounce here as well

[mfreeman451]

Fixed in UI cleanup work (#2310). Added:

• Edit button on device details page (RBAC protected - only visible to admins/owners)
• Editable form with fields: hostname, IP, type, vendor, model, tags
• Gateway field shown as read-only
• phx-debounce="300" on all editable inputs
• Cancel/Save buttons with proper state management

Note: Actual device update via Ash not yet implemented (shows 'coming soon' message). The UI infrastructure is in place.