:sig
String time_format_relative(u64 timestamp, String format_very_recent = "", u64 medium_recency_seconds = 0, String format_medium_recent = "", u64 not_recent_seconds = 0, String format_not_recent = "")

:params
timestamp : Unix timestamp to compare against the current time
format_very_recent : output format for very recent timestamps, defaults to `just now`
medium_recency_seconds : cutoff between the very-recent and medium-recent formats, defaults to `90`
format_medium_recent : output format for medium-recent timestamps, defaults to `%deltaM minutes ago`
not_recent_seconds : cutoff between the medium-recent and not-recent formats, defaults to `5400`
format_not_recent : output format for older timestamps, defaults to `%deltaH hours ago`
return value : a formatted relative-time string

:see
>time
>time_format_local
>time_format_utc

:content
Formats a timestamp relative to the current time using the same formatting engine as `time_format_local()` and `time_format_utc()`.

The formatter chooses one of three output formats:

- if `now - timestamp` is less than `medium_recency_seconds`, use `format_very_recent`
- else if it is less than `not_recent_seconds`, use `format_medium_recent`
- otherwise use `format_not_recent`

The relative-time tokens available in all time formatters are:

```text
%deltaS total elapsed seconds between the timestamp and now
%deltaM total elapsed minutes between the timestamp and now
%deltaH total elapsed hours between the timestamp and now
%deltad total elapsed days between the timestamp and now
%deltam total elapsed 30-day months between the timestamp and now
%deltaY total elapsed 365-day years between the timestamp and now
```

Default behavior examples:

```text
time_format_relative(time() - 12)
=> just now

time_format_relative(time() - 600)
=> 10 minutes ago

time_format_relative(time() - 7200)
=> 2 hours ago
```

Related:

- PHP: `DateTimeImmutable` diff formatting or libraries such as Carbon `diffForHumans()`
- JavaScript / Node.js: relative time helpers such as `Intl.RelativeTimeFormat`, `date-fns/formatDistanceToNow`, or Luxon