Major changes:
- Bump version from 3.3.0 to 3.3.1
- Update GasFeeStrategy API with min/max data size parameters
- Enhance trade return values with Optional<anyhow::Error> in buy/sell/sell_percent methods
- Fix PumpFun Mayhem mode fee recipient constant bug
- Standardize gas fee strategy parameters across all examples
- Update all examples to handle new triple return value (bool, Signature, Option<Error>)
- Rename add_* methods to set_* for clarity
- Simplify normal strategy API (remove TradeType param)
- Expose set/del methods for flexible strategy management
- Update docs and examples to match new API
BREAKING CHANGE: Method names changed for Gas Fee Strategy