Add SDXL bucket size node

README.md

@@ -9,6 +9,7 @@ The node is registered as:
 - `prompt_builder / SxCP Global Seed`
 - `prompt_builder / SxCP Seed Control`
 - `prompt_builder / SxCP Seed Locker`
+- `prompt_builder / util / SxCP SDXL Bucket Size`
 - `prompt_builder / SxCP Camera Control`
 - `prompt_builder / SxCP Camera Orbit Control`
 - `prompt_builder / SxCP Qwen Camera Translator`
@@ -309,6 +310,13 @@ you like, choose one `reroll_axis`, and connect its `seed_config`. All other
 axes stay frozen to `base_seed`; the rerolled axis follows `reroll_seed`, or the
 main prompt seed when `reroll_seed=-1`.
 
+`SxCP SDXL Bucket Size` randomly selects one of the built-in SDXL bucket
+resolutions and outputs `width`, `height`, and a `resolution` string. Use
+`orientation` to restrict the pool to portrait, square, or landscape. Leave
+`bucket_index=0` for random selection, or set `bucket_index` to pick a specific
+position inside the filtered pool. Connect `SxCP Global Seed` or Seed Locker's
+`seed_config` when the bucket choice must be reproducible.
+
 `SxCP Camera Control` and `SxCP Camera Orbit Control` output `camera_config`,
 which can be connected to the prompt builder or the Insta/OF pair node. They
 make camera/framing first-class instead of relying on a weak phrase inside the