devonfw-ide legacy support for maven

[hohwille]

With issue #280 and PR #305 we have implemented some change that prevents some kind of compatibility between devonfw-ide and IDEasy:

• devonfw-ide: settings/devon/conf/.m2/settings.xml -> conf/.m2/settings.xml
• IDEasy: settings/templates/conf/mvn/settings.xml -> conf/mvn/settings.xml, if template is not present use settings/devon/conf/.m2/settings.xml but keep same destination.

Both including replacement of variables.

As a result a user that has a project for devonfw-ide and wants to try out IDEasy will get a conf/mvn/settings.xml and then devonfw-ide will still expect conf/.m2/settings.xml (and conf/.m2/settings-security.xml).

Questions/approaches for a solution:

• should we stick to the template folder (settings/devon or new settings/templates) to act and behave like a template so that this alone decides if conf/.m2 or conf/mvn is used and not our hardcoded implementation? We could even avoid knowing where the file is located inside the template folder but just search for settings.xml and assume that this is for maven and apply the specific handling...
• or should we leave the code as is and consider settings/devon with all its handling just as some plain legacy support and write some documentation for users in mixed setups with devonfw-ide AND IDEasy that they should simply create a symbolic link/junction pointing from conf/.m2 to conf/mvn?