[26.2] Fix registry-based conditions in datapack registry and reloadable registry loading - #3451

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: gradle/actions/setup-gradle@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

[removal] parent(Identifier) in Builder has been deprecated and marked for removal

[dep-ann] deprecated item is not annotated with @deprecated

[removal] registryAccess() in IContext has been deprecated and marked for removal

[removal] BIOME_INFO_NOISE in Biome has been deprecated and marked for removal

[removal] BIOME_INFO_NOISE in Biome has been deprecated and marked for removal

[removal] BIOME_INFO_NOISE in Biome has been deprecated and marked for removal

[removal] getHighestSectionPosition() in ChunkAccess has been deprecated and marked for removal

[removal] move(FluidState,LivingEntity,Vec3,double) in FluidType has been deprecated and marked for removal

[removal] move(FluidState,LivingEntity,Vec3,double) in IFluidExtension has been deprecated and marked for removal