* 🗃️ new table for invitations to subscribe to brain
* ✨ new BrainSubscription class
* ✨ new subscription router
* 👽️ add RESEND_API_KEY to .env in BE
* 📦 add 'resend' lib to requirements
* ♻️ fix some stanGPT
* 🗑️ remove date input from fetch_user_id_from_credentials
* ♻️ refactor backend utils by splitting it into files
* 💡 comments for next actions to update /upload
* 🚚 move SupabaseProvider tp libs
* 🚚 move useAxios to hooks
* ♻️ refacto brain routes
* 🚨 update lintermfor paths
* ✨ new brain context provider
* ✨ new brain component in navbar
* 🚨 fix linter and async
* 🇸🇪 add feature flag for multiple-brains
* 🗃️ add new tables for multiple brains
* 🗑️ remove date input from fetch_user_id_from_credentials
* ✨ new /brain endpoints
* ♻️ refactor backend utils by splitting it into files
* 💡 comments for next actions to update /upload