Keyboard shortcuts for triage actions (approve / flag / trash)

Keyboard shortcuts for fast, one-handed triage of messages in the review/inbox view.

Suggested action keys:

• z = Approve
• x = Flag
• c = Trash

Note: message navigation already exists today via the up / down arrow keys (next / previous), so this request is specifically about the action shortcuts above.

Goal: triage large mailboxes quickly with one hand on the keyboard, without reaching for the mouse for every action.

Requested by a customer reviewing large eDiscovery exports (thousands of messages per project).