LocateNext 1.3.0

Adds NeoForge and Forge alongside Fabric, and fills in the missing Minecraft versions, taking the
build from 5 jars to 25.

Fabric gains 1.20.4, 1.20.6, 1.21.3, 1.21.4 and 1.21.5. NeoForge covers 1.20.4 through 1.21.11.
Forge covers 1.20.1 through 1.21.11. 26.1.2 and 26.2 stay Fabric-only.

Networking is where the loaders diverge most, so it stays in Net/ClientNet rather than at the
call sites, the same split 1.2.0 introduced for the payload-API boundary. Each loader needs its own
registration and send path, and within a loader those paths changed again mid-range: NeoForge 1.20.4
uses its fork's older RegisterPayloadHandlerEvent, 1.20.6 onward uses PayloadRegistrar, and
1.21.11 moves client-to-server sends onto ClientPacketDistributor. Forge keeps SimpleChannel
throughout, but 1.20.1 predates CustomPacketPayload entirely, and 1.21.11's EventBus 7 moves
command, keybind, tick and datapack-sync events off the shared bus onto dedicated ones.

Two version boundaries in the existing source turn out to have been wrong, and adding versions in the
1.20.2 to 1.20.6 window is what exposed them. ResourceLocation's named factory arrived in 1.21, not
1.20.5, so 1.20.5 and 1.20.6 still take the public constructor. SavedData.Factory arrived in 1.20.2
but did not take a registry lookup until 1.20.5, which is three eras rather than the two the code
assumed, and both NeoForge and Forge ship their own 1.20.4 variants on top of that. Neither could
fire before, because no node existed in that window.

Loader-specific entrypoints live in flat per-loader files rather than nested conditionals, because
Stonecutter does not resolve //? if markers nested inside another conditional's commented-out
region.

Known gap: every jar builds, but the NeoForge and Forge nodes have not been run in-game. Fabric
1.21.1 and 1.21.11 remain the only paths tested end to end. Forge 1.21.11 is the least proven of the
set, since EventBus 7 is a large change and it has only been compiled against.