Access colormaps folder in scripts realpath (not symlink path)

[mefrediani]

When we link the plot script to the simulation folder, it can't find the colormaps folder with the reflectivity colorscale.

Add this line at the start:
SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))

Replace the statement in line 262 (elif os.path.exists(colorfile:=f"colormaps/{cmapname}.yaml"):) with

    elif (colorfile_info := resolve_custom_colormap_file(cmapname))[0]:
        colorfile, _ = colorfile_info

You can add more information to the raise statement (line 279):

        _, searched = resolve_custom_colormap_file(cmapname)
        raise ValueError(
            f"Requested color map {cmapname} is not valid. "
            f"Checked built-in matplotlib colormaps and custom files: {searched}"
        )

And add this function:

def resolve_custom_colormap_file(cmapname: str):
    """
    Resolve custom colormap YAML by checking:
    1) explicit user-provided path (with/without .yaml),
    2) script-local colormaps directory,
    3) current-working-directory colormaps directory.
    """
    searched = []

    # Allow explicit path-like values in config (absolute or relative)
    if os.path.isabs(cmapname) or os.path.sep in cmapname:
        explicit = cmapname if cmapname.endswith(".yaml") else f"{cmapname}.yaml"
        searched.append(explicit)
        if os.path.exists(explicit):
            return explicit, searched

    candidates = [
        os.path.join(SCRIPT_DIR, "colormaps", f"{cmapname}.yaml"),
        os.path.join(os.getcwd(), "colormaps", f"{cmapname}.yaml"),
    ]
    # Remove duplicates while preserving order.
    candidates = list(dict.fromkeys(candidates))
    for candidate in candidates:
        searched.append(candidate)
        if os.path.exists(candidate):
            return candidate, searched

    return None, searched