Double-click message to reply / edit (opt-in setting)

Problem

This is purely a quality of life feature, not a problem

Proposed solution

Add an opt-in setting that allows the following:

• Double click a message from a user other than yourself to quickly reply to that message, with a toggleable default reply ping on/off
• Double click a message sent by yourself to edit its contents.
• Toggle to only activate if shift or ctrl is being held whilst double clicking
• Toggle to only activate after three clicks