Close sidebar on mobile resolution immediately after changing the route

[Antreesy]

☑️ Resolves

• Follow up for fix closing the left sidebar on click automatically #9508
• Previously we're waiting for server response to emit the event, that toggle sidebar. Now we do it after changing the route
  • Emitting the event comes from participantsStore async action joinConversation, which is called only on switching the conversations
  • Action is also called on App.vue beforeMount(), but sidebar toggling is also handling by App itself

🖼️ Screenshots

🏚️ Before

route-slow.mp4

🏡 After

route-fast.mp4

🚧 Tasks

• Visual check
• Code review
• Testing for all 'joined-conversation' emit cases

🏁 Checklist

• ⛑️ Tests (unit and/or integration) are included or not required
• 📘 API documentation in docs/ has been updated or is not required
• 📗 User documentation in https://github.com/nextcloud/documentation/tree/master/user_manual/talk has been updated or is not required
• 🔖 Capability is added or not needed

[Antreesy]

/backport to stable27

[szaimen]

Tested and works. Thanks for fixing this! :)

[szaimen]

/backport to stable26