Allow admins to hide event export buttons

[ChristophWurst]

This contributes the first part of #3993.

The patch adds a simple config switch. There are shared environments where Nextcloud is only used on web and users are not supposed to export/download event data to a local disk.

I will update the admin calendar docs accordingly. The config switch can be done via CLI with

php -f occ config:app:set calendar hideEventExport --value=yes

• TODO rename download to export

[codecov]

Codecov Report

Merging #3995 (6bf4d07) into main (59cc000) will increase coverage by 0.01%.
The diff coverage is 40.00%.

@@             Coverage Diff              @@
##               main    #3995      +/-   ##
============================================
+ Coverage     29.45%   29.47%   +0.01%     
  Complexity      323      323              
============================================
  Files           220      220              
  Lines          7577     7583       +6     
  Branches       1002     1002              
============================================
+ Hits           2232     2235       +3     
- Misses         5345     5348       +3     

Flag	Coverage Δ
javascript	20.82% <40.00%> (+<0.01%)	⬆️
php	67.44% <ø> (+0.04%)	⬆️

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Impacted Files	Coverage Δ
src/views/Calendar.vue	0.00% <ø> (ø)
src/views/EditSidebar.vue	0.00% <0.00%> (ø)
src/views/EditSimple.vue	0.00% <0.00%> (ø)
src/store/settings.js	100.00% <100.00%> (ø)
...ud/apps/calendar/lib/Controller/ViewController.php	100.00% <0.00%> (ø)

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[raimund-schluessler]

Maybe I don't understand it, but how does that help without a change of server? The url is still accessible and serves the data.

[ChristophWurst]

Maybe I don't understand it, but how does that help without a change of server? The url is still accessible and serves the data.

That is correct from a technical PoV. This is really about what options we give the users explicitly. The Files app has a similar feature. You can hide the download button, while technically files could still be acquired. It's 🤷 but also 🙈 to put it into emojis :)

[ChristophWurst]

Maybe I don't understand it, but how does that help without a change of server? The url is still accessible and serves the data.

#3993 (comment) for more context :)

[GretaD]

looks good

done