Summary

research wait --import-all uses the command's --timeout value as the total retry budget for import retries, but source add-research --import-all currently falls back to the CLI helper default of 1800 seconds because that command does not expose a timeout flag.

Why this matters

This is not a functional bug, but it means the same import operation has different retry budgets depending on which CLI command invokes it.

Proposed change

Add a --timeout option to notebooklm source add-research and pass it through to the internal import_with_retry() helper so both commands are consistent.

Notes

• Current behavior is reasonable and should remain the default until the option is added.
• This is follow-up polish from PR fix: preserve deep research reports and poll tasks #193, not a blocker for that fix.