fix: cross-platform postinstall patch — replace macOS-only sed with Node script

Author: piotrekwitkowski

package.json

@@ -10,7 +10,7 @@
     "build": "astro build",
     "generate:props": "tsx scripts/extract-props.ts",
     "preview": "astro preview",
-    "postinstall": "sed -i '' \"s/vnode.type !== ClientOnlyPlaceholder:/vnode.type !== ClientOnlyPlaceholder \\&\\& !vnode.type.includes('-'):/\" node_modules/astro/dist/runtime/server/jsx.js"
+    "postinstall": "node scripts/patch-astro.mjs"
   },
   "dependencies": {
     "@astrojs/mdx": "^5.0.3",

scripts/patch-astro.mjs

@@ -0,0 +1,15 @@
+import { readFileSync, writeFileSync } from 'node:fs';
+
+const file = 'node_modules/astro/dist/runtime/server/jsx.js';
+const content = readFileSync(file, 'utf8');
+const patched = content.replace(
+  'vnode.type !== ClientOnlyPlaceholder:',
+  "vnode.type !== ClientOnlyPlaceholder && !vnode.type.includes('-'):"
+);
+
+if (content === patched) {
+  console.log('⚠️  Astro patch target not found — may already be fixed or changed');
+} else {
+  writeFileSync(file, patched);
+  console.log('✅ Patched astro JSX handler for custom element hydration');
+}