Clicking a link of the sidebar will now open the drawer and load the correct channel.
This solution should correctly solve these cases:
closing drawer, clicking sidebar channel, should open the drawer on correct channel
visiting /chat then visiting / and clicking sidebar channel, should open full page chat on correct channel
This commits makes sure we correctly wait for the end of the transition to reopen the drawer on the correct channel/view. Also fixes a bug when previous URL was `/` and causing a double transition.
Also adds end to end system tests to ensure navigation scenarios are working correctly. This separation will make it easier to implement state in/out from chat.
