Enhance DateTimeType to parse ZonedDateTime with time-zone ID

[jlaur]

This DSL rule:

rule "Test"
when
    Item Test changed to ON
then
    var zoned = ZonedDateTime.parse("2024-12-22T16:29+01:00")
    logInfo("zoned to item", zoned.toString)
    TestDateTime.postUpdate(zoned.toString)

    zoned = (TestDateTime.state as DateTimeType).getZonedDateTime()
    logInfo("zoned from item", zoned.toString)

    TestDateTime.postUpdate(zoned.toString)
end

generates the following output in 4.3:

2024-12-23 00:27:00.168 [INFO ] [nhab.core.model.script.zoned to item] - 2024-12-22T16:29+01:00
2024-12-23 00:27:00.169 [INFO ] [ab.core.model.script.zoned from item] - 2024-12-22T16:29+01:00[Europe/Copenhagen]
2024-12-23 00:27:00.170 [WARN ] [b.core.model.script.actions.BusEvent] - Cannot convert '2024-12-22T16:29+01:00[Europe/Copenhagen]' to a state type which item 'TestDateTime' accepts: [DateTimeType, UnDefType].

Until 4.2 this rule worked, because getZonedDateTime() returned the same ZonedDateTime as provided when creating the DateTimeType. Since it didn't necessarily contain time-zone ID but only offset (e.g. "2024-12-22T16:29+01:00"), DateTimeType.parse would then be able to parse it in some scenarios. Now, it contains the time-zone ID (e.g. "2024-12-22T16:29+01:00[Europe/Copenhagen]") always, which DateTimeType.parse is not able to parse (and never was).

To make this rule compatible I would propose to add support for parsing a full ZonedDateTime string that includes time-zone ID. If this is accepted, I think it should also be cherry-picked into 4.3.x for immediate value. i.e. to fix rules that might have been broken by 4.3. By the time we reach 5.0, users would otherwise have been forced to refactor their rules already.

See https://community.openhab.org/t/datetime-conversion-after-update-to-4-3-0/161053/1

Regression of #3583

[openhab-bot]

This pull request has been mentioned on openHAB Community. There might be relevant details there:

https://community.openhab.org/t/datetime-conversion-after-update-to-4-3-0/161053/5

[kaikreuzer]

lgtm, thanks!

[kaikreuzer]

Backported to 4.3.x.