fix sidebar root node links

[d-buchmann]

Link sidebar root nodes to their corresponding "new" route.
Fixes #954

[codecov]

Codecov Report

Attention: Patch coverage is 43.75000% with 9 lines in your changes missing coverage. Please review.

Project coverage is 59.86%. Comparing base (c445359) to head (a32c875).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/Services/Trees/TreeViewGenerator.php	43.75%	9 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #957      +/-   ##
============================================
+ Coverage     59.73%   59.86%   +0.12%     
- Complexity     6036     6038       +2     
============================================
  Files           529      529              
  Lines         20588    20602      +14     
============================================
+ Hits          12298    12333      +35     
+ Misses         8290     8269      -21     

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[jbtronics]

Thank you.

I changed it so that for now we still have the original behavior, that the root nodes for everything besides projects redirect to "show all parts". I left your code in a way that it should be easily to make the behavior configurable when the new settings system works...