Allow to prevent @all for non-moderators

[nickvergessen]

Remaining task from #6339

[vitormattos]

Will be necessary to add conversation level setting to prevent use @all in a conversation.

[vitormattos]

@nickvergessen could you check if the follow scenario is ok to cover this issue?

  Scenario: Toggle the usage of @all in a group by non moderators
    Given user "participant1" creates room "room" (v4)
      | roomType | 2 |
      | roomName | room |
    And user "participant1" sets setting "prevent_non_moderators_notify_all" to "1" with 200 (v1)
    And user "participant1" adds user "participant2" to room "room" with 200 (v4)
    And user "participant2" joins room "room" with 200 (v4)
    When user "participant2" sends message "Hi @all" to room "room" with 201
    Then user "participant1" has the following notifications
      | app | object_type | object_id | subject |
    When user "participant1" sets setting "prevent_non_moderators_notify_all" to "0" with 200 (v1)
    And user "participant2" sends message "Bye @all" to room "room" with 201
    Then user "participant1" has the following notifications
      | app    | object_type | object_id    | subject                                                          |
      | spreed | chat        | room/Bye @all | participant1-displayname mentioned everyone in conversation room |

[nickvergessen]

prevent_nom_moderatos_… you mean _non_moderators_ ?

We might even want to reject the message instead of still posting it? Silently ignoring it doesn't sound like the best idea to me.
Also the @all should no longer be returned by the autocomplete suggestions

For the test you should use 2 different messages, maybe Hi @all and Bye @all to confirm which message is causing the notification at the end.

[vitormattos]

Scenario fixed.

[vitormattos]

@nickvergessen now is the mention scenario:

  Scenario: Toggle the usage of @all and try to use mentions
    Given user "participant1" creates room "room" (v4)
      | roomType | 2 |
      | roomName | room |
    And user "participant1" adds user "participant2" to room "room" with 200 (v4)
    And user "participant2" joins room "room" with 200 (v4)
    When user "participant1" sets setting "prevent_non_moderators_notify_all" to "1" with 200 (v1)
    Then user "participant2" gets the following candidate mentions in room "room" for "all" with 400
    When user "participant1" sets setting "prevent_non_moderators_notify_all" to "0" with 200 (v1)
    Then user "participant2" gets the following candidate mentions in room "room" for "all" with 200
      | id           | label                    | source |
      | all          | room                     | calls  |

[vitormattos]

@nickvergessen is this app setting, right? Or is a setting by room?

[nickvergessen]

per room

[vitormattos]

I will change from prevent_non_moderators_notify_all to can_mention_everyone to have a short parameter.