Feature Request: Subtitle color customization fields in /v2/video/generate

Hi,

I'm building an automated video pipeline using the HeyGen API and I need granular control over subtitle colors to match my brand identity.

After contacting support, I was confirmed that color customization is not yet available via API — only preset_name, font_size, font_family, font_weight, position, alignment, and highlight are currently supported.

The HeyGen UI already exposes these controls for presets like "Elevated" (text color, background color, highlight color, outline color, shadow color), so the underlying logic exists — it just needs to be exposed in the API.

Requested fields in the subtitles object:

{
  "text_color": "#FFFFFF",
  "background_color": "#000000",
  "highlight_color": "#FFD700",
  "outline_color": "#000000",
  "shadow_color": "#333333"
}

This would be extremely valuable for developers building automated content pipelines where consistent branding across videos is essential.

Happy to help test if needed. Thanks!