Add input fields for Maven coordinates in UI

[geziefer]

The current version of the starter generates default Maven coordinates:

	<groupId>org.eclipse</groupId>
	<artifactId>jakartaee-hello-world</artifactId>
	<version>0.1-SNAPSHOT</version>

As it is common in other starters (e.g. SpringBoot, MicroProfile, Quarkus, OpenLiberty, ...) we should allow for editing those values in UI before project creation.