Migrate to vue 3

Fixes #1215 (closed), #1297 (closed), #1298 (closed), #1326 (closed), #1363 (closed), #1377 (closed), #1379 (closed), #1381 (closed), #1471 (closed), #1536 (closed), #1547 (closed), #1567 (closed), #1581 (closed), #1635 (closed), #1636 (closed), #1647 (closed), #1759 (closed), #1762 (closed), #1766 (closed), #1777 (closed), #1796, #1802 (closed), #1828 (closed), #1829 (closed), #1836 (closed), #1844 (closed), #1845 (closed)

I've reverted ec630a23, so #739 (closed) and #1812 (closed) will be tracked by wvffle/gapless-play branch when this id merged to develop