Add ability to view score statistics without watching replay

[peppy]

Discussed in #14469

While we do intend to move more statistics to the raw score object (ie. the thing we receive from the server), this won't ever cover all statistics we want displayed on the results screen. Optimally, when a replay is locally available statistics should be processed automatically in the background and displayed when ready.

For cases with an online replay available, a button or text link should be available in the place a user would expect statistics to trigger the download and begin processing score after that.

[rszyma]

Currently, the moment user exits result screen to the song select the statistics (like UR) are gone. Until the proposed headless calculation of stats is implemented, how about keeping those stats cached for a while longer, e.g. until end of session, or at least until starting another map? Personally it would solve my annoyance with it (that I tend to immediately exit to song select, then right after click back to see extended stats, but they're gone)