🔨 refactor(endpoints.py): remove unused get_flow_from_token function and HTTPBearer import

🐛 fix(endpoints.py): add check for flow data before processing
🔨 refactor(process.py): add type hints to process_tweaks function
The get_flow_from_token function and HTTPBearer import are removed as they are not used in the code. A check for flow data is added before processing to avoid errors when the flow data is None. The process_tweaks function is updated to include type hints for the graph_data and tweaks parameters.