Fix: Reduce API key to 16 hex chars, use 60 byte safety margin for bcrypt

Fix: Reduce API key length to 20 hex chars, add truncate to verify, fix logging

Fix: Truncate API key to 72 bytes for bcrypt compatibility

A3: Add API key authentication and GET /me endpoint

Fix Core Phase 1: Add health endpoint, __init__.py files, and router registration

Add app.py for Hugging Face Spaces deployment and fix config

Restructure project: add models, alembic migrations, and core modules