Vote and state verb menus (redesign stage C)

[jinyeow]

Part of the lazygit-inspired redesign — see ADR 0022 (stage C).

What to build

Transient-style option menus on the shared menu component: v opens a vote menu (approve / approve with suggestions / wait for author / reject / reset) wherever voting works today, and s on a work item opens a state menu listing the item type's actual states. Selection applies the action and reports to the message bar.

Acceptance criteria

• v shows the five vote options with key hints; choosing one casts the vote (replaces the current vote prompt)
• s lists the selected work item's valid states fetched for its type; choosing one transitions the item
• Menu content builders are pure and unit-tested; existing vote/state behaviour reachable and unchanged in effect

Blocked by

• Reusable menu component + executable ? help (redesign stage C) #20 (Reusable menu component + executable ? help)