[Feature]: Added option to change SAM model folder location

[Enchante503]

Expected behavior

I'm new to writing code, so I'll have to scrutinize the code, but it seems to work.

#scripts_sam_model_dir = os.path.join(scripts.basedir(), "models/sam")
try:
    sam_models_dir = shared.opts.sam_models_dir
except AttributeError:
    sam_models_dir = ""

if len(sam_models_dir) == 0 or sam_models_dir.isspace():
    scripts_sam_model_dir = os.path.join(scripts.basedir(), "models/sam")
else:
    scripts_sam_model_dir = os.path.expanduser(sam_models_dir)



def on_ui_settings():
    section = ('segment_anything', "Segment Anything")
    shared.opts.add_option("sam_use_local_groundingdino", shared.OptionInfo(False, "Use local groundingdino to bypass C++ problem", section=section))
    shared.opts.add_option("sam_models_dir",
                           shared.OptionInfo(
                                default="",
                                label="Segment Anything Models Directory",
                                component=gr.Textbox,
                                component_args={"interactive": True},
                                section=section))