[Feature Request] Add short description labels to mode names when cycling with shift+tab

Feature Request

Describe the feature
When cycling through modes using shift+tab (the chat:cycleMode action), the mode name shown in the UI (e.g., auto, plan) does not include any description of what each mode does. For non-English speakers especially, this is not immediately clear.

Proposed solution
Display a short description alongside the mode name when switching, e.g.:

• auto → auto — Claude decides when to use tools
• plan → plan — read-only, outputs a plan without executing

Ideally the descriptions could be localizable so users can configure a preferred language.

Why it matters
New users are often unsure what switching modes does. A short inline label would reduce friction without requiring documentation lookups.