feat: show precise time on hovering the time of a message

[nushea]

Description

This simple PR makes hovering over a message's time show the full time and date of when it was sent, which helps track messages across time, especially when you are searching or moving around to find some specific messages. This feature is the most useful for compact view users.

It follows the date format set up by the user (Settings → General → Date & Time → Date Format)

Screenshots of how it looks:

Fixes #2699
(accidentally closed #2710 by renaming the branch to give my local branches proper names ~-~ without realizing it automatically closes them on github/cinny)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings