Add Cognito list-users command to learnings and update Sprint 4 completion status

Initialize authentication learning project with DevCollab Platform

Remove .direnv files from git tracking

Remove obsolete AWS PDF documentation files

Replace AWS PDF documentation with txt format and update learning materials

Added rust and zig directories

Add Cognito authentication to file-sharing service

Complete Sprint 3: File metadata storage with DynamoDB

Add DynamoDB metadata storage and file listing to file-sharing service

Add README with hero image

Complete file-sharing-service Sprint 1 and expand teaching plan

checking in initial projects/file-sharing-service/plan.md

Add AWS learning environment with offline documentation and tooling

initial commit