Add stringBytesUniq and stringBytesEntropy

Why it matters

These functions help users identify potentially random or encrypted data within string columns by quantifying the uniqueness and entropy of byte values, which are common indicators of such data types. This facilitates data analysis tasks like data quality checks and anomaly detection.

How to use it

Use stringBytesUniq to count unique bytes in a string and stringBytesEntropy to calculate the entropy of bytes in a string. They can be applied directly in SQL queries on string fields, for example:

SELECT stringBytesUniq(column_name), stringBytesEntropy(column_name) FROM table_name;