[Bug] `--flow-shift` ignored on flux_flow models when leaving `--prediction` argument to default

[stduhpf]

Git commit

48e0a28

Command-line arguments used

.\bin\Release\sd.exe --diffusion-model ....\ComfyUI\models\diffusion_models\flux1-dev-iq4_nl.gguf --t5xxl ....\ComfyUI\models\clip\t5xxl_fp16.safetensors --clip_l --t5xxl ....\ComfyUI\models\clip\clip_l.safetensors -p "a lovely cat holding a sign says 'Flux cpp'" --cfg-scale 4.0 --sampling-method euler -v --flow_shift 6s 'Flux cpp'" --cfg-scale 1.0 --sampling-method euler -v --flow-shift 6

Steps to reproduce

.\bin\Release\sd.exe --diffusion-model ..\..\ComfyUI\models\diffusion_models\flux1-dev-iq4_nl.gguf --t5xxl ..\..\ComfyUI\models\clip\t5xxl_fp16.safetensors --clip_l --t5xxl ..\..\ComfyUI\models\clip\clip_l.safetensors -p "a lovely cat holding a sign says 'Flux cpp'" --cfg-scale 1.0 --sampling-method euler -v --flow_shift [1|6] [--prediction flux_flow]

	--flow_shift 1	--flow_shift 6	default
default prediction
--prediction flux_flow

What you expected to happen

The same result should happen with or without --prediction flux_flow, regardless of the value of --flow-shift.

What actually happened

--flow-shift is ignored by default. That's because https://github.com/leejet/stable-diffusion.cpp/blob/master/stable-diffusion.cpp#L763-L771 doesn't use the value of sd_ctx_params->flow_shift, but https://github.com/leejet/stable-diffusion.cpp/blob/master/stable-diffusion.cpp#L722-L727 does.
(Also I beleive the default shift when overriding prediction seems wrong, it should be 1, not 3)