Update processing status to display percentage

[itsafuu]

Addition to #149 the screen should display percentage. PR #190 will need to be merged before this can be accomplished. getProcessingStatus will return a result with result.status and result.percentage. Current polling rate is every 1 second, I believe that if the status is PROCESSING that we should probably poll more often for the duration for displaying the percentage more accurately.

Additionally, it seems like this screen blocks all input? The user should still be able to use the app regularly while this screen is displaying.