Align client mod construction with server and construct before Minecraft.<init> is called

[shartte]

We currently construct mod objects "somewhere" inside of the constructor of Minecraft and recently moved the location for neoforged/NeoForge#1830
This caused unexpected issues due to shifting availability of some fields of Minecraft.

We should rip the bandaid off, so to speak, and align mod construction on clients with the approach taken on servers: Construct the mods much earlier (after bootstrap, but before any other global state is initialized), and offer events that align with the lifecycle of the "client" (==Minecraft), such as ClientStartingEvent, ClientStartedEvent, ClientStoppingEvent, ClientStoppedEvent.

Overall this makes the contract much clearer: During mod construction, Minecraft.instance is null, and the modder has to subscribe either to events they care about (same as now, such as RegisterClientReloadListenersEvent instead of accessing the resource manager directly), or subscribe to the client lifecycle events that make their contract much more explicit than now (are the fields of Minecraft initialized or not).

[marchermans]

Agreed this would make stuff so much cleaner.