feat(examples): add nonce and token balance monitoring capabilities

- feat(examples): add nonce_listen_example for nonce account tracking
- feat(examples): add token_balance_listen_example for balance monitoring
- feat(parser): implement NonceAccountEvent with nonce state parsing
- feat(types): add AccountNonce event type to filtering system
- docs: update README with new monitoring examples
- chore: bump version to 0.4.2

src/streaming/event_parser/common/types.rs

@@ -141,6 +141,7 @@ pub enum EventType {
     AccountRaydiumCpmmAmmConfig,
     AccountRaydiumCpmmPoolState,
 
+    AccountNonce,
     AccountCommon,
 
     // Common events
@@ -163,6 +164,8 @@ pub const ACCOUNT_EVENT_TYPES: &[EventType] = &[
     EventType::AccountRaydiumClmmTickArrayState,
     EventType::AccountRaydiumCpmmAmmConfig,
     EventType::AccountRaydiumCpmmPoolState,
+    EventType::AccountCommon,
+    EventType::AccountNonce,
 ];
 pub const BLOCK_EVENT_TYPES: &[EventType] = &[EventType::BlockMeta];
 
@@ -228,6 +231,7 @@ impl fmt::Display for EventType {
             EventType::AccountRaydiumCpmmAmmConfig => write!(f, "AccountRaydiumCpmmAmmConfig"),
             EventType::AccountRaydiumCpmmPoolState => write!(f, "AccountRaydiumCpmmPoolState"),
             EventType::AccountCommon => write!(f, "AccountCommon"),
+            EventType::AccountNonce => write!(f, "AccountNonce"),
             EventType::BlockMeta => write!(f, "BlockMeta"),
             EventType::Unknown => write!(f, "Unknown"),
         }