feat: improve subject generation workflow

deploy/.env.production.example

@@ -22,7 +22,9 @@ LLM_API_KEY=
 ASR_MODEL=whisper-1
 ASR_FALLBACK_MODEL=gemini-2.5-flash
 TRANSLATE_MODEL=gemini-2.5-flash
-REWRITE_MODEL=gemini-2.5-pro
+GPT_TEXT_MODEL=gpt-4o
+REWRITE_MODEL=gpt-4o
+VISION_MODEL=gpt-4o
 PRODUCT_VIEW_MODEL=gpt-image-2
 IMAGE_BASE_URL=https://ai.skg.com/ezlink/v1
 IMAGE_API_KEY=
@@ -33,9 +35,14 @@ SUBJECT_ASSET_IMAGE_MODELS=gpt-image-2
 # Optional outbound proxy for AI gateway calls. Leave blank on normal VPS networking.
 AI_HTTP_PROXY=
 
+# Optional TikTok download login state for yt-dlp. Keep cookies files private.
+YTDLP_COOKIES_FILE=
+YTDLP_COOKIES_FROM_BROWSER=
+
 # Audio rewrite and Azure OpenAI TTS
 AUDIO_REWRITE_MODEL=gemini-2.5-pro
 AUDIO_PRODUCT_BRIEF="SKG smart massage products for daily neck, shoulder, back, eye, knee, and foot relaxation. Keep claims premium, clean, credible, and non-medical."
+# Voice is fixed to Azure OpenAI in the backend.
 VOICE_PROVIDER=azure_openai
 AZURE_OPENAI_BASE_URL=https://ai.skg.com/azure
 AZURE_OPENAI_API_KEY=
@@ -43,13 +50,7 @@ AZURE_TTS_MODEL=gpt-4o-mini-tts
 AZURE_TTS_VOICE_ID=alloy
 AZURE_TTS_VOICE_POOL=alloy,verse,shimmer
 AZURE_TTS_PATH=/audio/speech
-
-# Legacy MiniMax TTS fallback; not the default voice provider.
-MINIMAX_API_KEY=
-MINIMAX_TTS_BASE_URL=https://api.minimax.io
-MINIMAX_TTS_MODEL=speech-2.8-turbo
-MINIMAX_TTS_VOICE_ID=English_expressive_narrator
-MINIMAX_TTS_VOICE_POOL=English_magnetic_voiced_man,English_Upbeat_Woman,English_MaturePartner
+AZURE_TTS_PATHS=/audio/speech,/v1/audio/speech
 
 # Video generation. Use SKG Doubao / Seedance gateway in production.
 POE_API_BASE_URL=https://api.poe.com/v1