fix: show unambiguous date for older "Last login" timestamps

[ManojPawar2]

Overview

The Last login field in the User Information panel was ambiguous for any login that wasn't from today. formatTimestamp rendered non-today timestamps as just a weekday and time — e.g. Tuesday 10:49 PM — with no date. A login from 90 days ago looked identical to one from earlier this week, so there was no way to tell how old it actually was.

Fixes #1313

Root cause

packages/react/src/lib/formatTimestamp.js formatted non-today timestamps using only the weekday name:

return isDifferentDay
  ? `${date.toLocaleDateString('en-US', { weekday: 'long' })} ${formattedTime}`
  : formattedTime;

The weekday repeats every 7 days, so the output is ambiguous for anything older than a week. This is also inconsistent with the rest of the app, which already shows full dates (formatTimestampGetDate, and date-fns formatting in Message.js).

Fix

Render non-today timestamps with an explicit short month, day and year, while keeping today's logins as time-only:

return isDifferentDay
  ? `${date.toLocaleDateString('en-US', {
      month: 'short',
      day: 'numeric',
      year: 'numeric',
    })}, ${formattedTime}`
  : formattedTime;

Resulting output:

Timestamp | Before | After -- | -- | -- 90 days ago | Tuesday 10:49 PM | Mar 3, 2026, 10:49 PM A week ago | Wednesday 9:25 AM | Jun 18, 2026, 9:25 AM Today | 9:25 AM | 9:25 AM (unchanged)

• Files changed: 1 — packages/react/src/lib/formatTimestamp.js

• Scope: formatTimestamp is used only by the "Last login" field, so the change is fully contained and does not affect message timestamps or any other view.

Acceptance Criteria fulfillment

• Non-today "Last login" values show an unambiguous date with year

• Logins of different ages are now visually distinguishable

• Today's logins still display only the time

• Output style is consistent with date formatting used elsewhere in the app

How to test

1. Open the User Information panel for a user whose last login is older than a few days.

2. Confirm the Last login field shows a full date with year, e.g. Mar 3, 2026, 10:49 PM, instead of just a weekday.

3. Open the panel for a user who logged in today and confirm it still shows only the time, e.g. 9:25 AM.

Video/Screenshots

N/A — text-only formatting change in the Last login field.

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