Deploy tutorial feature and recent fixes

Fix interactive chat wizards and surface in-progress creations on workshop pages.

Switch all LLM calls to GPT-5.4 and load secrets from shared.env.

Replace MongoDB with SQLite + bucket-mounted file uploads

Replace single-image compose with hot-reload compose as default; remove docker-compose.dev.yml

Initial CU Student AI Project Helper: FastAPI, Gemini, Mongo, React SPA