fix: avoid inlineDynamicImports ignored with codeSplitting warning when using Vite 8 (#15647)

Closes #15646.

Fixed by not defining inlineDynamicImports when building service worker
with Vite 8.

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Author: kiwixz

.changeset/small-lines-care.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+fix: avoid inlineDynamicImports ignored with codeSplitting warning when using Vite 8

packages/kit/src/exports/vite/build/build_service_worker.js

@@ -110,7 +110,7 @@ export async function build_service_worker(
 					// .mjs so that esbuild doesn't incorrectly inject `export` https://github.com/vitejs/vite/issues/15379
 					entryFileNames: `service-worker.${is_rolldown ? 'js' : 'mjs'}`,
 					assetFileNames: `${kit.appDir}/immutable/assets/[name].[hash][extname]`,
-					inlineDynamicImports: !is_rolldown
+					inlineDynamicImports: !is_rolldown ? true : undefined
 				}
 			},
 			outDir: `${out}/client`,