add date and time information above totp setup instructions

[masteradhoc]

Fixes #357

What?

Adds a one-line server date/time display to the TOTP setup UI so users can verify the server clock and timezone when registering an authenticator app.

Why?

TOTP relies on timestamps; a misconfigured server clock or timezone causes OTPs to be invalid. Showing the current server date/time helps site administrators and users quickly confirm the server time is correct and avoid TOTP failures.

How?

Inserted a single translatable line above the QR/secret instructions in user_two_factor_options():
Uses date format and time format set in wordpress settings to format it appropriately.

Testing Instructions

1. go to edit a user
2. you can see the TOTP setup in the usual way
3. apply changes
4. refresh the page and see the server date/time formatted in your local site format

Screenshots or screencast

1. Version with timezone associated to a city and date format F j, Y and timeformat g:i a

2. Version with timezone associated set to UTC+1 and date format d.m.Y and timeformat H:i

Changelog Entry

Added - Show server date/time on TOTP setup so administrators can verify timezone/clock to avoid invalid OTPs

[github-actions]

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Co-authored-by: masteradhoc <masteradhoc@git.wordpress.org>
Co-authored-by: kasparsd <kasparsd@git.wordpress.org>

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