Option to hide collections in webapp

[davidwaroquiers]

Partially solves #1965

This removes (read: hides them conditionally to the VUE_APP_HIDE_COLLECTIONS environment option) all collections related views/options. As already explained in #1965, access rights with collections can be misleading. This PR does not remove collection-related backend parts (database, end points etc ...).

With the soon to be included tags features, collections somehow become an alternative (although with some slightly different behavior) to tags. Both features are still compatible with each other for those who would require/prefer to have both.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.48%. Comparing base (ddb057c) to head (7e89685).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2113   +/-   ##
=======================================
  Coverage   82.48%   82.48%           
=======================================
  Files          91       91           
  Lines        8782     8782           
=======================================
  Hits         7244     7244           
  Misses       1538     1538           

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[davidwaroquiers]

This is ready for review @ml-evs

I've also opened #2153 that is the "same" except that it also disables the backend. I let you decide which one is best. This one is obviously smaller (no backend changes), while the other one is somehow "complete" for the disabling of the collections and has a few more changes related to backend.