GUI Planner DFlash2 Draft

This release contains fully finetuned draft weights derived from:
z-lab/Qwen3.8-27B-DFlash2
Revision: 50307d4c4cde6860d4eee73e2547cd786fe8e8a4
https://huggingface.co/z-lab/Qwen3.8-27B-DFlash2/tree/50307d4c4cde6860d4eee73e2547cd786fe8e8a4

The upstream draft is distributed under Apache License 2.0. Original work
and implementation are attributed to the upstream model and DFlash project.

Changes in this release: all draft backbone, dynamic-convolution and
candidate-selector parameters were finetuned for GUI planning for two
epochs, then exported as BF16 safetensors. The original block-8 configuration
is preserved; block 12 is selected only through inference configuration.
The compatible target, tokenizer, processor and datasets are separate assets.

The optional serve_planner.py helper applies the same Qwen XML whitespace
policy used in the reported benchmark. It is provided under Apache 2.0.