[odan]

Add ArrayReader::getDateTime() and ArrayReader::findDateTime(). Both return a DateTimeImmutable and do not require Chronos.

Accepted values:

• A date string
• An existing DateTimeImmutable, including Chronos
• A mutable DateTime
• An integer or finite float Unix timestamp, parsed with DateTimeImmutable::createFromTimestamp()
• getDateTime() throws InvalidArgumentException when the value is missing or not a date. findDateTime() returns null instead.

Note:

createFromTimestamp() requires PHP 8.4, so support for PHP 8.2 and 8.3 is dropped.

Follow-up to #11.