tts-captioned-video: all caption_* options sent thru the JSON body are ignore by service

[askb]

2025-08-26 00:57:55.962 | INFO     | api_server.v1_media_router:generate_captioned_video:558 - Background task added for captioned video generation with ID: video_8ef46b30-9211-43e0-aa44-0bf680da8d57.mp4 | {}
      INFO   172.18.0.1:49136 - "POST                                           
             /api/v1/media/video-tools/generate/tts-captioned-video HTTP/1.1"   
             200
2025-08-26 00:57:55.963 | DEBUG    | video.tts:kokoro_english:313 - Starting TTS generation with kokoro | {'voice': 'af_jessica', 'speed': 0.8, 'text_length': 124, 'device': 'cpu'}
2025-08-26 00:58:01.414 | DEBUG    | video.tts:kokoro_english:360 - TTS generation completed with kokoro | {'voice': 'af_jessica', 'speed': 0.8, 'text_length': 124, 'device': 'cpu', 'execution_time': 5.450441837310791, 'audio_length': 8.8, 

From the Docker service logs it does not show the captions settings being processed?

Example body sent to tts-captioned-video API:

{{ 

[
  `background_id=${$('Upload image to server').item.json.file_id}`,
  $json.tts_audio_id ? `audio_id=${$json.tts_audio_id}` : false,
  $json.tts_audio_id ? '' : `text=${encodeURIComponent($('Loop Over Items').item.json.text)}`, `language=en`,
  $json.tts_audio_id ? '' :  `kokoro_voice=${$('Configure TTS').item.json.kokoro_voice.replace(/\"/g, '')}`,
  $json.tts_audio_id ? '' : `kokoro_speed=${$('Configure TTS').item.json.kokoro_speed}`,
`caption_config_line_max_length=50`,
`caption_config_line_count=2`,`caption_config_font_size=60`,
`caption_config_font_bold=true`,
`caption_config_subtitle_position=bottom`,
`caption_config_stroke_size=3`,
`caption_config_stroke_color=${encodeURIComponent('#000')}`,
`caption_config_font_color=${encodeURIComponent('#fff')}`,
`caption_config_shadow_blur=8`].filter(Boolean).join('&') 

}}

```

All the `caption_*` values gets ignore by the service. Is this a bug that needs to be fixed?