migrate to vue 3

[SebastianKrupinski]

Summary

• Resolves: https://github.com/nextcloud/calendar/issues/7684
• Migrate to vue 3

[SebastianKrupinski]

Initial testable vue 3 migration

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 0.00%. Comparing base (50fc39c) to head (8f12201). :warning: Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #7697       +/-   ##
==========================================
- Coverage   11.06%       0   -11.07%     
==========================================
  Files         327       0      -327     
  Lines       62364       0    -62364     
  Branches      918       0      -918     
==========================================
- Hits         6900       0     -6900     
+ Misses      55328       0    -55328     
+ Partials      136       0      -136     

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[GVodyanov]

Fixed this:

Before	After

[GVodyanov]

I added the new datepicker, however it requires this: https://github.com/nextcloud-libraries/nextcloud-vue/pull/8009