Fix build, re-publish @mysten/kms (#20125)

## Description 

Build will always treat `src` as the base for outputs when building.

## 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.

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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: 
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- [ ] CLI: 
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.changeset/good-students-care.md

@@ -0,0 +1,5 @@
+---
+'@mysten/kms': patch
+---
+
+Fix exports on the bundled package

sdk/build-scripts/src/utils/buildPackage.ts

@@ -60,6 +60,7 @@ async function buildCJS(
 		entryPoints,
 		outdir: 'dist/cjs',
 		sourcemap: true,
+		outbase: 'src',
 		...buildOptions,
 	});
 	await buildTypes('tsconfig.json');
@@ -90,6 +91,7 @@ async function buildESM(
 		target: 'es2020',
 		entryPoints,
 		outdir: 'dist/esm',
+		outbase: 'src',
 		sourcemap: true,
 
 		...buildOptions,