- Add execution prevention to down_for_encryption with RAISE EXCEPTION
- Rename functions: up_sql_for_table → up_for_encryption, down_sql_for_table → down_for_encryption
- Change function signatures to use direct arguments instead of options
- Add comprehensive warnings about bits immutability in README and docs
- Improve PostgreSQL function validation: combine checks for bits and key
- Add validation for negative values and edge cases (bits < 2, key < 0)
- Add explanatory comments for trigger logic and sanity checks
- Update documentation with detailed safety warnings and usage examples

Breaking changes:
- Function names and signatures changed
- down_for_encryption now requires manual safety guard removal to execute