refactor: restructure event handling from trait objects to enum pattern

- Convert UnifiedEvent from trait object (Box<dyn UnifiedEvent>) to concrete enum type
  - Remove match_event! macro in favor of native match expressions
  - Simplify event metadata access: event.event_type() -> event.metadata().event_type
  - Unify event callback signatures: Fn(Box<dyn UnifiedEvent>) -> Fn(UnifiedEvent)
  - Update all example code to use the new enum-based event system
  - Optimize type system to reduce runtime overhead and improve type safety

  Affected scope:
  - Core event parser and processor
  - All protocol event definitions (PumpFun, PumpSwap, Bonk, Raydium series, etc.)
  - gRPC and Shred streaming modules
  - All example code

src/streaming/event_parser/mod.rs

@@ -3,38 +3,4 @@ pub mod core;
 pub mod protocols;
 
 pub use core::traits::UnifiedEvent;
-pub use protocols::types::Protocol;
-
-/// 宏：简化 downcast_ref 模式匹配
-///
-/// # 使用示例
-/// ```
-/// use sol_trade_sdk::event_parser::match_event;
-///
-/// match_event!(event, {
-///     PumpSwapCreatePoolEvent => |typed_event| {
-///         println!("CreatePool event: {:?}", typed_event);
-///     },
-///     PumpSwapDepositEvent => |typed_event| {
-///         // 处理存款事件
-///     },
-/// });
-/// ```
-#[macro_export]
-macro_rules! match_event {
-    ($event:expr, {
-        $($event_type:ty => $handler:expr),* $(,)?
-    }) => {
-        $(
-            if let Some(typed_event) = $event.as_any().downcast_ref::<$event_type>() {
-                $handler(typed_event.clone());
-            } else
-        )*
-        {
-            // 默认情况：什么都不做
-        }
-    };
-}
-
-// 重新导出宏以便于使用
-pub use match_event;
+pub use protocols::types::Protocol;