fix: use qdrant-client[fastembed] extra for proper integration

fix: remove unused unstructured dependency to resolve onnxruntime version conflicts

fix: upgrade unstructured to resolve onnxruntime conflict with fastembed

fix: resolve pillow dependency conflict with fastembed

feat: replace OpenAI embeddings with local FastEmbed models for semantic memory

fix: bcrypt 4.0 compatibility patch and support for passwords > 72 bytes

fix: add missing dependencies itsdangerous and starlette for session middleware

feat: integrate Google OAuth, ArXiv discovery and project-based analysis

Initial clean backend deployment