Delay HUD Hiding and Add Average Offset to PlayerScreenResults

[BashhScriptKid]

• [x] Allow player to still see the scores for longer instead of instantly disappearing on track clear ~~- Show indicator for chart loading~~ (Skipped per request by duducat)
• [x] Added 'Average offset' to PlayerScreenResults

For "Last-play based offset calibration, inspired from osu!lazer", I'm not good enough to implement the whole thing, but I have added scaffold logic (means 'half-finished but doesn't break anything') for someone else to implement it completely

[BashhScriptKid]

The formatting part is mostly unintentional, it's my IDE's work :')