Fix InvalidPathError: whitelist OUT_DIR for Gradio 5 file serving

Gradio 5's launch() only serves files from the CWD, the system temp dir, or
allowed_paths. Generated images/docx are written under config.OUT_DIR
(/data/out on HF persistent storage), so returning those paths from the
pipeline made the Gallery/File outputs raise InvalidPathError right after
generation finished. Pass allowed_paths=[str(config.OUT_DIR)] to launch();
Gradio's allowlist check is an ancestor-or-equal match, so this one entry
covers every per-run subfolder.

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

app.py

@@ -140,4 +140,7 @@ if __name__ == "__main__":
         server_name="0.0.0.0",
         server_port=7860,
         show_api=False,  # avoid API-schema generation edge cases
+        # Generated images/docx live under config.OUT_DIR (e.g. /data/out on HF
+        # persistent storage), which Gradio 5's file-serving allowlist otherwise rejects.
+        allowed_paths=[str(config.OUT_DIR)],
     )