feat: auth page redesign and full bug audit fixes

feat: add Supabase auth + 5 new pipeline stages

feat: PDF and DOCX stage/full-build reports for HITL and autonomous flow

fix: add missing Depends import to billing.py

fix: strict_gates defaults to false, remove dead code

security: fix ENCRYPTION_KEY default, /verify-payment broken access control, path-traversal in design_name endpoints, /designs header-spoofing

fix: default strict_gates=False for cloud, create PDK_ROOT dir in container

fix: ensure litellm is installed for LLM backend, .env never overrides HuggingFace secrets, add /ping endpoint

fix: add litellm openai/ prefix for NVIDIA model, inject provider env vars, robust LLM init

fix: strip vendor-specific LLM kwargs; expose per-backend errors

debug: expose LLM error in /health; pin crewai==1.9.3 + litellm==1.81.8

fix: add Groq as LLM fallback (NVIDIA → Groq → Local)

fix: point Vercel frontend to HF Space backend

feat: rewarding build UX + Docker fixes + web docs cleanup

feat: add expandable artifact file list to HITL approval cards + download endpoint

feat: Supabase auth + Razorpay billing + fix API double-URL bug

feat: add skip coverage option to Design Studio and Human In Loop Build pages

feat: add HITL webapp with 3 UX improvements

feat(core): integrate core modules, update UI and docs

chore: security audit, fix API leak, and update gitignore

fix: replace native EventSource with fetchEventSource to bypass ngrok block

fix: Remove unused vars to fix Vercel strict TS build

feat: universal chip support, claude theme, and SFT logging export