feat(shred): tx_index, Migrate without CPI, merge fix, doc limits

- Add tx_index to TransactionWithSlot (entry index), pass to parser
- Emit PumpFun Migrate even when no CPI (shred gets instruction-only)
- Merge: only overwrite Create/CreateV2 with CPI when value non-default
- Rename transaction_index -> tx_index across codebase
- Add docs/SHREDSTREAM_LIMITATIONS.md (ALT/CPI limits, field completeness)
- Comment shred path: static_account_keys only, no inner_instructions

Made-with: Cursor

examples/grpc_example.rs

@@ -113,9 +113,9 @@ async fn test_grpc() -> Result<(), Box<dyn std::error::Error>> {
 fn create_event_callback() -> impl Fn(DexEvent) {
     |event: DexEvent| {
         println!(
-            "🎉 Event received! Type: {:?}, transaction_index: {:?}",
+            "🎉 Event received! Type: {:?}, tx_index: {:?}",
             event.metadata().event_type,
-            event.metadata().transaction_index
+            event.metadata().tx_index
         );
         match event {
             DexEvent::BlockMetaEvent(e) => {

examples/parse_tx_events.rs

@@ -177,7 +177,7 @@ async fn get_single_transaction_details(signature_str: &str) -> Result<()> {
                 .unwrap()
                 .as_micros() as i64;
             let bot_wallet = None;
-            let transaction_index = None;
+            let tx_index = None;
 
             let protocols = vec![
                 Protocol::Bonk,
@@ -206,7 +206,7 @@ async fn get_single_transaction_details(signature_str: &str) -> Result<()> {
                 &accounts,
                 &inner_instructions_vec,
                 bot_wallet,
-                transaction_index,
+                tx_index,
                 callback,
             )
             .await?;

examples/shred_example.rs

@@ -57,9 +57,9 @@ async fn test_shreds() -> Result<(), Box<dyn std::error::Error>> {
 fn create_event_callback() -> impl Fn(DexEvent) {
     |event: DexEvent| {
         println!(
-            "🎉 Event received! Type: {:?}, transaction_index: {:?}",
+            "🎉 Event received! Type: {:?}, tx_index: {:?}",
             event.metadata().event_type,
-            event.metadata().transaction_index
+            event.metadata().tx_index
         );
         match event {
             DexEvent::BlockMetaEvent(e) => {