Add loading/disabled state to TokenField component

[mdiniz97]

The TokenField component lacks a disabled/loading state, which is common in form components and needed for consistent UX.

Current behavior:

• No way to disable the component
• No visual indication when the field is loading or disabled
• Missing ARIA attributes for disabled state

Proposed solution:

• Add prop to TokenField component
• Add visual disabled state styling
• Add proper ARIA attributes (, )

Expected usage:

Type: UI improvement / Accessibility