Create README.md for CryptoAdvisor AI project

feat: configure CORS in backend and HttpClient in angular

feat: implement financial advisor logic and portfolio analysis

Ignore appsettings.json

feat: implement ICryptoAdvisorService and advice use case

feat: add Type column to Transactions table

feat: implement virtual cash balance logic using TransactionType

feat: implement GetPortfolio use case with LINQ aggregation

feat: implement CreateTransaction use case and application DI

feat: add TransactionsController and create transaction endpoint

feat: implement Transaction repository and register in DI

feat: create and apply initial database migration

feat: isolate dependency injection into infrastructure extensions

feat: create AppDbContext and configure infrastructure layer

feat: feat: add transaction entity with domain validation