fix(ExAppNotifier): First check if any exapps enabled

[marcelklehr]

To avoid unnecessary work and logs

[Copilot]

Pull Request Overview

This PR adds an early guard clause in the prepare method to avoid unnecessary work and logs when no external apps are enabled.

• Introduces a check for an empty ExApps list and throws UnknownNotificationException if none are configured.
• Retains existing behavior of throwing the same exception when a specific app is unknown.

Comments suppressed due to low confidence (1)

lib/Notifications/ExAppNotifier.php:39

• New behavior for an empty ExApps list should be covered by a unit test to ensure the exception is thrown as expected.

		if (count($this->service->getExAppsList()) === 0) {

[oleksandr-nc]

Is it just to hide the debug log line?

Because getExAppsList and getExApp use the same code.

[marcelklehr]

Yes

[oleksandr-nc]

another option - maybe we just remove that debug line?

[marcelklehr]

As you wish. I was trying to keep the behavioural change minimal :)

[oleksandr-nc]

Of course, I prefer to remove this debug line (it's a less significant change), but I am happy with the current approach.