Cleanup in ASArray class initializer
Port all Vector members to TS implementations

This reduces startup time by ~180ms, with the Vector classes now contributing a total of ~8ms instead of ~190ms. It also should make all those methods quite a bit faster.

Additionally, this is a substantial cleanup and net removal of several 100 lines of gnarly code.
Change TimelineBuffer to default to using a system startup timestamp as their start time

This gets timelines of the different systems synchronized and makes it much easier to see where we spend our time during startup. (E.g., right now we spend ~370ms parsing JS before we even reach a state where our runtime starts initializing.)