🐛🎨 Pass WEBSERVER_FOLDERS flag to frontend and use it

[odeimaiz]

What do these changes do?

🐛 Pass disabled folders plugin to frontend
🎨 Frontend uses the plugin flag
🐛 Frontend: do not fetch folders for guest users

Related issue/s

includes #6205

How to test

Dev-ops checklist

• No ENV changes or I properly updated ENV (read the instruction)

[sanderegg]

thanks

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.0%. Comparing base (cafbf96) to head (3726eac).
Report is 445 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##           master   #6206      +/-   ##
=========================================
- Coverage    84.5%   82.0%    -2.6%     
=========================================
  Files          10     577     +567     
  Lines         214   29433   +29219     
  Branches       25     234     +209     
=========================================
+ Hits          181   24158   +23977     
- Misses         23    5215    +5192     
- Partials       10      60      +50     

Flag	Coverage Δ
integrationtests	64.8% <ø> (?)
unittests	87.5% <ø> (+2.9%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
.../simcore_service_webserver/application_settings.py	98.2% <ø> (ø)

... and 586 files with indirect coverage changes