[Feature] Adding `wait_for_idle` in the constructor of `TealAppDriver`

[vedhav]

          How about adding the `wait_for_idle` here instead of using it after `TealAppDriver$new` on each single test?

I also suggest re-implementing wait_for_idle to increase the timeout of the TealAppDriver, wdyt?

      private$set_active_ns()
      self$wait_for_idle()
    },
    wait_for_idle = function(duration = 500, timeout = 20000) {
      super$wait_for_idle(duration = duration, timeout = timeout)
    },

_Originally posted by @averissimo in https://github.com/insightsengineering/teal/pull/1127#discussion_r1521365360_

[m7pr]

This is great and I already need that! I think the app$click() could also benefit from the extension of $wait_for_idle() as those are the two situations in which I always use $wait_for_idle

[m7pr]

Hey @averissimo and @vedhav - I created a PR in here for implement this, but left 2 questions for a serious discussion https://github.com/insightsengineering/teal/pull/1171