FarlandsTweaks Core 1.3 - BFC 2.2 / Embeddium PHASE2 compatibility layer

1) Legacy OcclusionCuller replacement
- Keeps cancelling only BFC's legacy sodium.MixinOcclusionCuller when the installed
  Embeddium no longer exposes OcclusionCuller.isSectionVisible.
- Adds a PHASE2 replacement at computePassVisibility(...).
- BFC early chunk occlusion is applied only to visibility bit 0 (main camera pass).
- Higher PHASE2 TerrainVisibilityPass bits remain untouched for shader/mod compatibility.

2) BFC Async Chunk Rebuild preservation
- Restores BFC's original render-thread cancellation for the single-pass
  findVisible(Visitor, Viewport, float, boolean, int) path.
- PHASE2 multi-pass findVisible remains synchronous on purpose because BFC 2.2's async
  state does not carry the new extra frustum/pass arrays. This is a compatibility
  fallback: Async Chunk Rebuild remains available for the normal single-pass path
  instead of corrupting additional visibility-pass render lists.

3) Extended BlockEntity bounds guard
- Keeps BFC block-entity culling enabled globally.
- Only block entities with non-finite or >1.5-block render AABB extent on any axis
  bypass BFC's block-entity culling decision.
- Normal block entities remain fully culled by BFC.
- Covers the demonstrated Hexerei Drying Rack false-culling case.

No BFC feature is globally disabled by this patch. Tick culling is untouched.
