Fix CLI --mode animator not exporting AnimationClip with --fbx-animation all, and add support for --fbx-uvs-as-diffuse, add FBX ASCII format support for CLI

[haojiezhe12345]

1. Fix --fbx-animation all not working with --mode animator

with CLI option --mode animator --fbx-animation all it should export Animator + AnimationClips, but it fails to add AnimationClips because the type is not added to the o_exportAssetTypes list

as seen in ExportAnimator(), Studio.cs:961, it has an exportAllAnimations flag which adds AnimationClips to animationList, but because all AnimationClips is filtered out, nothing will be added

public static void ExportAnimator()
{
    var animationList = CLIOptions.o_fbxAnimMode.Value == AnimationExportMode.Auto
        ? null
        : new List<AssetItem>();
    // `animationList` exists if `--fbx-animation` is set to all/skip

    var exportAllAnimations = CLIOptions.o_fbxAnimMode.Value == AnimationExportMode.All;
    // true if `--fbx-animation all`

    Logger.Info("Searching for Animator assets...");
    var animatorList = new List<AssetItem>();
    foreach (var asset in parsedAssetsList) // `AnimationClip`s is filtered out
    {
        switch (asset.Type)
        {
            case ClassIDType.Animator:
                animatorList.Add(asset);
                break;
            case ClassIDType.AnimationClip when exportAllAnimations:
                animationList?.Add(asset); // never reaches
                break;

as observed, parsedAssetsList is added by ParseAssets(), and the exportable filtering logic is located at Studio.cs:332

isExportable = CLIOptions.o_exportAssetTypes.Value.Contains(asset.type); // filter by `o_exportAssetTypes`
if (isExportable || (CLIOptions.f_loadAllAssets.Value && CLIOptions.o_exportAssetTypes.Value == CLIOptions.o_exportAssetTypes.DefaultValue))
{
    fileAssetsList.Add(assetItem);
}

by adding ClassIDType.AnimationClip to o_exportAssetTypes in WorkMode.Animator, AnimationClips are kept and animations will be exported in the model

it is sure that AnimationExportMode.All (--fbx-animation all) is designed to use here because this is the only reference to it

2. Fix the 'unsupported' message for --fbx-uvs-as-diffuse in --mode animator

--fbx-uvs-as-diffuse is designed to work with FBX export where WorkMode.SplitObjects does, but WorkMode.Animator also does this job. Both these two modes should accept this flag

3. Added CLI option --fbx-ascii-format

With this switch, FBX will be exported in ASCII format, otherwise in Binary.