Receives a report and creates a string email content using the html template called balance.

Receives records and calculates: - Total balance - Transactions count by month - Average credit by month - Average debit by month Then returns it as Report */.

Reads a file from the given path and returns the buffer e.g buffer(0xc000570940).

getEnv retrieves the environment variable "ENV" and defaults to the provided fallback if not set.

Reads a buffer, removes the header and returns a slice with the records.

Rounds a float to 2 decimals.

go:embed templates/balance.html.