fix(build): make manualChunks a function and raise macOS target for Vite 8

Vite 8 bundles with Rolldown, which rejects an object-form manualChunks
("Expected Function but received Object") and broke the PWA and Tauri builds.
Convert both to the function form.

Rolldown's worker bundler (esbuild) also cannot lower the inlined dcm2niix
worker to the safari14 target, so bump the macOS/WebKit floor to safari15
(macOS 12+ ships Safari 15+).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: korbinian90

apps/desktop-tauri/vite.config.ts

@@ -87,8 +87,10 @@ export default defineConfig({
   build: {
     outDir: 'build',
     sourcemap: true,
-    // Tauri uses Chromium on Windows/Linux and WebKit on macOS
-    target: process.env.TAURI_PLATFORM === 'windows' ? 'chrome105' : 'safari14',
+    // Tauri uses Chromium on Windows/Linux and WebKit on macOS.
+    // safari15 is the floor: Vite 8's worker bundler (esbuild) cannot lower
+    // the inlined dcm2niix worker to safari14, and macOS 12+ ships Safari 15+.
+    target: process.env.TAURI_PLATFORM === 'windows' ? 'chrome105' : 'safari15',
     // Don't minify for debug builds
     minify: !process.env.TAURI_DEBUG ? 'esbuild' : false,
     chunkSizeWarningLimit: 1000,
@@ -97,8 +99,11 @@ export default defineConfig({
         entryFileNames: 'assets/[name]-[hash].js',
         chunkFileNames: 'assets/[name]-[hash].js',
         assetFileNames: 'assets/[name]-[hash].[ext]',
-        manualChunks: {
-          vendor: ['preact', '@preact/signals'],
+        // Rolldown (Vite 8) requires manualChunks to be a function, not an object
+        manualChunks: (id) => {
+          if (id.includes('/preact/') || id.includes('/@preact/signals')) {
+            return 'vendor'
+          }
         },
       },
       onwarn: (warning, warn) => {

apps/pwa/vite.config.ts

@@ -31,7 +31,7 @@ const gitRepoUrl = getGitRepoUrl()
 const isProd = process.env.NODE_ENV === 'production'
 // Support PR previews with PR_NUMBER environment variable
 const prNumber = process.env.PR_NUMBER
-const baseUrl = isProd 
+const baseUrl = isProd
   ? (prNumber ? `/niivue-vscode/pr-${prNumber}/` : '/niivue-vscode/')
   : '/'
 
@@ -212,8 +212,11 @@ export default defineConfig({
         entryFileNames: 'assets/[name]-[hash].js',
         chunkFileNames: 'assets/[name]-[hash].js',
         assetFileNames: 'assets/[name]-[hash].[ext]',
-        manualChunks: {
-          vendor: ['preact', '@preact/signals'],
+        // Rolldown (Vite 8) requires manualChunks to be a function, not an object
+        manualChunks: (id) => {
+          if (id.includes('/preact/') || id.includes('/@preact/signals')) {
+            return 'vendor'
+          }
         },
       },
       // Ensure virtual modules are properly handled