Add application logs section when using tokio-console

[Milo123459]

Something to see & filter the logs from your application.

[hawkw]

Yeah, we'd definitely like to eventually have a way to stream a log of all tracing events from the program. One thing we've also considered is adding a way to filter event logs by task, and display a log of all the events that occurred within a particular task in the Task Details view. Of course, we could also show event logs for all tasks,

Some design considerations:

• This should probably be a separate RPC than the main Instrument::watch_updates RPC. We're already streaming a lot of data from the instrumented application, and most of the views the console currently provides probably won't display logs by default. Therefore, we'll probably want to have a way to toggle on and off log streams separately from other data streams, so that we're only streaming them as needed.
• How would we want to filter what logs are displayed?
• Since we can stream logs as structured data rather than as strings, we can probably display them in some much more interesting ways than just a bunch of lines of text --- e.g. some data can be conditionally hidden or shown. However, we probably want to start with something simple and then iterate on it.

[Milo123459]

Filtering should just be pressing ctrl+f and showing a text box