revert: port back to 7860 - HF Space uses 7860

fix: change port from 7860 to 8080 - HF Space proxy expects port 8080

fix: set ASPNETCORE_ENVIRONMENT=Production in Dockerfile, create /data/data dir

feat: integrate FreeDeepseekAPI background proxy and routing in AIService

fix: change Dockerfile port to 7860 for HuggingFace Spaces

fix: optimized Dockerfile, backend AI service, and gitignore

init