[ts sdk] bug fix on names replacement (#20577)

## Description 

The plugin would replace things when it shouldn't! 

## Test plan 

How did you test the new or updated feature?

---

## Release notes

Check each box that your changes affect. If none of the boxes relate to
your changes, release notes aren't required.

For each box you select, include information after the relevant heading
that describes the impact of your changes that a user might notice and
any actions they must take to implement updates.

- [ ] Protocol: 
- [ ] Nodes (Validators and Full nodes): 
- [ ] Indexer: 
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK:
- [ ] REST API:

.changeset/pretty-frogs-cough.md

@@ -0,0 +1,5 @@
+---
+'@mysten/sui': patch
+---
+
+Fixes replacements on `namedPackagesPlugin` to only replace the package target if it is a mvr name.

sdk/typescript/src/transactions/plugins/utils.ts

@@ -94,8 +94,11 @@ export const replaceNames = (builder: TransactionDataBuilder, cache: NamedPackag
 		if (name.includes(NAME_SEPARATOR) && !cache.packages[name])
 			throw new Error(`No address found for package: ${name}`);
 
-		nameParts[0] = cache.packages[name];
-		tx.package = nameParts.join('::');
+		// Replace package name with address.
+		if (name.includes(NAME_SEPARATOR)) {
+			nameParts[0] = cache.packages[name];
+			tx.package = nameParts.join('::');
+		}
 
 		const types = tx.typeArguments;
 		if (!types) continue;