docs: clarify quantization support matrix

Signed-off-by: Hongsheng Liu <liuhongsheng4@huawei.com>

docs/user_guide/examples/offline_inference/text_to_video.md

@@ -143,7 +143,8 @@ python text_to_video.py \
 - `--enable-layerwise-offload`: enable layerwise offloading on DiT modules.
 - `--frame-rate`: generation FPS for pipelines that require it (e.g., LTX2).
 - `--audio-sample-rate`: fallback audio sample rate when the pipeline returns audio.
-- `--quantization`: quantization method (`fp8` for FP8, `gguf` for GGUF).
+- `--quantization`: online quantization method, for example `fp8`; supported
+  pre-quantized checkpoints are normally auto-detected from checkpoint metadata.
 - `--flow-shift`: scheduler flow_shift parameter.
 - `--lora-path`: path to PEFT LoRA adapter folder or checkpoint file.
 - `--lora-scale`: scale factor for LoRA weights.

docs/user_guide/examples/online_serving/diffusers_pipeline_adapter.md

@@ -90,8 +90,8 @@ vllm serve "Qwen/Qwen-Image" \
     --quantization-config '{"method": "fp8"}'
 ```
 
-Other vLLM-Omni quantization methods, such as `gguf`, `modelopt`, `mxfp4`,
-`mxfp8`, serialized checkpoints, static FP8 configs, and layer-name skip lists
+Other vLLM-Omni quantization methods, such as `modelopt`, `mxfp4`, `mxfp8`,
+serialized checkpoints, static FP8 configs, and layer-name skip lists
 such as `ignored_layers`, are intentionally not translated by this compatibility
 shortcut. Use Diffusers-native configuration through `diffusers_load_kwargs` or
 a native vLLM-Omni pipeline for those cases.