[Feature] Implement update_weights_from_disk for SGLang-D (Diffusion … (#18306)

Co-authored-by: zhaochenyang20 <zhaochen20@outlook.com>

python/sglang/multimodal_gen/test/server/testcase_configs.py

@@ -28,6 +28,8 @@ from typing import Sequence
 from sglang.multimodal_gen.runtime.platforms import current_platform
 from sglang.multimodal_gen.runtime.utils.perf_logger import RequestPerfRecord
 
+DEFAULT_SMALL_MODEL = "Tongyi-MAI/Z-Image-Turbo"
+
 
 @dataclass
 class ToleranceConfig:
@@ -339,8 +341,6 @@ TURBOWAN_I2V_sampling_params = DiffusionSamplingParams(
     fps=4,
 )
 
-DEFAULT_SMALL_MODEL = "Tongyi-MAI/Z-Image-Turbo"
-
 # All test cases with clean default values
 # To test different models, simply add more DiffusionCase entries
 ONE_GPU_CASES_A: list[DiffusionTestCase] = [