fix: replace networkidle0 with load + image-complete wait for file:// pages

networkidle0 is unreliable for large local documents; explicit image
decode check is more robust.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/pdf.js

@@ -101,7 +101,13 @@ async function generate() {
   page.setDefaultNavigationTimeout(120_000);
   page.setDefaultTimeout(120_000);
 
-  await page.goto(`file://${inputPath}`, { waitUntil: 'networkidle0', timeout: 120_000 });
+  await page.goto(`file://${inputPath}`, { waitUntil: 'load', timeout: 120_000 });
+
+  // Wait until every <img> has finished decoding (handles large local images)
+  await page.waitForFunction(
+    () => [...document.images].every(img => img.complete && img.naturalHeight > 0),
+    { timeout: 120_000 },
+  );
 
   // Write to temp file first so Ghostscript can read it
   await page.pdf({