feat: v0.5.5 - enhanced priority fee system and dependency updates

- Update solana-streamer-sdk to 0.4.1
- Refactor priority fee API (custom_buy_tip_fee → custom_priority_fee)
- Simplify documentation and clean up examples

BREAKING CHANGE: priority fee parameter type changed

examples/raydium_cpmm_trading/src/main.rs

@@ -162,7 +162,6 @@ async fn raydium_cpmm_copy_trade_with_grpc(trade_info: RaydiumCpmmSwapEvent) ->
             Box::new(buy_params),
             None,
             true,
-            None,
         )
         .await?;
 
@@ -192,7 +191,6 @@ async fn raydium_cpmm_copy_trade_with_grpc(trade_info: RaydiumCpmmSwapEvent) ->
             Box::new(sell_params),
             None,
             true,
-            None,
         )
         .await?;